We were looking for my friend's piano's serial number and found the hammers looking like this.... Is this what they're supposed to look like?

The fallboard is probably pressing on the black keys.
Edit: The music desk actually.

That makes a TON of sense, lol. We're idiots. Sorry.

Of course it might have been this:
https://www.shutterstock.com/image-illustration/black-white-piano-keys-hand-drawn-1072774043
Ian

That made my day.

Ouch, that must be pretty bad for the music stand and the keys?

Well, we flipped the fallboard down to check kind of carelessly. This is not how she typically closes the fallboard, in which she puts everything back carefully, and nicely lays the felt over the keys.