That weren't corpses but the remains of the Inhumans after their Terrigenesis proces. They weren't killed by Hydra, because he needed them alive for when Hive comes back.

We know that the ATCU was a HYDRA front.
I always assumed that because of this, the Inhumans were being killed without the knowledge of Rosalind.
Truth be told, I had such a hard time enjoying Season three that I never paid that much attention to the ATCU storyline (in the later episodes).

As previously stated, they were cocoons.
Skye's cocoon shattered into tiny bits because she quaked out of hers. If you remember Joey's, there were some large pieces when he hatched; Andrew also, IIRC.
RIP 616
#TimeForMoreAmadore

That is a possibility. Yet it seems like the cocoons break apart into mostly little pieces when an inhuman emerges, and what she found looked like complete bodies. Although, considering how Trip crumbled apart in the Kree temple, you are probably correct.
~Oh, I'm well aware it's not a picnic, Mr. Save the Day~ (Fitz, Agents of Shield)

I haven't seen it since it aired so my memory is fuzzy, but I thought what she found were the terrigenesis cocoon shells.

Someone probably remembers better than I do - but I thought they had killed any Inhumans that they didn't deem useful enough?
Reading my signature constitutes admission that I am correct. (Too late)