The next several days, despite being categorized as rest, relaxation and recovery, were spent in a competitive battle of one-upsponyship. Whenever Rarity would try to do something nice for Rainbow, she had to do something nice in turn. The same was true in the opposing direction, as well. Rainbow couldn't do something nice for Rarity without her being so full of gratitude that she had to do something in return. The gifts just kept growing bigger and more bombastic, starting with Rarity making a hammock for Rainbow, and Rainbow making a long strand of rope directing them more accurately to the water source, allowing them to drink at night. At most recent, Rarity had trimmed some shrubs in the shape of Rainbow Dash, and Rainbow had built up the source to make it dribble water from above in some mock-up of a shower.
Rainbow was walking along the beach, trying to come up with something to balance out the massage Rarity had promised her after her shower. She was running out of ideas, and she really hoped Rarity was almost out, as well. She really hated the idea that she could no longer share her gratitude.
As she rounded a bend, her eyes lit up. An ironclad ship, whose name she was unable to read from this distance, was anchored about two kilometres off the coast. Even more of a shock, a small boat was rowing toward the island, and seemed to be directed at their camp. No doubt, they had seen the slab and were coming to investigate.
She took off the baskets she'd filled with coconuts, and stashed them in the rocks. In the best case, she wouldn't need them, and in the worst, she'd be back to pick them up. Rainbow dashed through the trees, rather than along the beach, just in case the ponies approaching were not friendly. She would need to watch them from behind some foliage, first, and perhaps bolt off to inform Rarity.
The boat pushed itself up on the beach, and four stallions hopped off. They looked a bit rough, as though they'd been at work for weeks with little rest. The scruffiest of them all looked familiar, somehow, as if she'd seen him before, but she couldn't place it. He was sporting a ragged, dark blue mane and tail and a pair of goggles with a yellow strap. His wings obscured his cutie mark.
"St. Louvia," he said, reading the wreckage. His voice was hoarse and gravelly. "This is the ship that went down. More importantly, there's no way in Equestria that this is how it landed here." He poked his head into the shelter, then came back up. "Almost looks comfortable in there. Somepony's definitely here." He coughed into his hoof a few times, then spat something out. He approached the firepit and looked in. "Undoubtedly, whoever's here is still alive. We're looking for warm bodies, men. Spread out and meet back here in half an hour. The islet's not that big, so you'll have found something, at least."
Immediately, two of the sailors started down the path towards where Rarity was showering. In order to reach her first, Rainbow would be required to either rush through the brush, making all manner of noise and giving away her position, or jump out into the open where everypony could see her. It didn't take her any time at all to make her decision as to how to proceed. Even if it meant she would be taken in her place, Rainbow couldn't risk any more damage to Rarity.
She leaped out of the bushes, tackling the pegasus she'd almost recognised to the sand and pinning him down. This close, she could see his green eyes through the goggles. She kept a stone face throughout, unsure of where she knew him from until a big smile stretched across his face. "We've been looking all over for you, Dash!" He reached up and hugged her.
She backed off a bit to let him stand. She knew him from somewhere, he knew her by name, and he was happy to see her. That led her to the conclusion that this was indeed a rescue party, and not a band of pirates. As he stood up, she caught sight of his cutie mark, and realisation washed over her. "Soarin!" She immediately returned the hug. "What happened to you?"
"We've been all over the place for the last week," he explained as the other sailors gathered. "Princess Celestia received a report of the shipwreck, and noting that there were four souls unaccounted for among the survivors, sent us out to look for you."
Rainbow swallowed hard "Four?"
"You're the third we've found," assured Soarin. "The other two are okay, if a little bit worse for wear. One was starving, both were dehydrated, but both are being brought back to health as we speak. Just one more to go, and we can call this mission a success." His smile faded, and he placed a hoof on Rainbow's shoulder. "The bad news is that we haven't found Rarity yet. She's still missing."
"She's in the shower, actually," corrected Rainbow. "She should be back soon."
Soarin coughed into his hoof again, spitting out another gob. "Do you want somepony to go let her know that we're waiting?"
"No, she'll be here soon," nodded Rainbow. "If she's not, I'll fetch her myself. What's wrong with your throat?"
"Just a cold. We've been in and out of the water and in some cramped spaces while we were looking."
"That explains it."
Rainbow spent the next ten minutes relaying to Soarin everything that had happened, starting just before the kraken attack and glossing over most of the details. She also gave him a tour of their sleeping quarters, as small as it was, and he was pretty impressed that they'd done all of this themselves with only stone tools.
In the end, Rainbow did have to go collect Rarity. After finishing her cold shower, she'd gone to the other side of the island to dry in the sun and pick up some more coconuts, not knowing that Rainbow had already done so. As soon as she heard there was a boat there to pick them up, she raced back to the camp, leaping into the arms of a sailor, who carried her back to the boat. The shelter would stay as it was, in the event that somepony else washed up after a shipwreck. Rainbow stayed by Soarin's side, not really caring if she caught his cold. They were going home. That was all that mattered to them.