Reassembling Rainbow Dash should be straightforward, but Applejack and Fluttershy are missing bits.

8004871 This may well be a plot point! And well, Applejack's bits are still technically there on the field. You just might need to patiently scrape it all up

They seem to be having fun

The funniest part is fluttershy would do this and would probably smile while it happens.