Quest item respawns the next cycle

[WillaWisps]

Giga-robo's leg was randomized to be on the couch. I picked it up and completed the cutscene where I connect the leg to the robot during the day. The next night, I see it again (maybe it replaced a respawnable item?).
Also it has no label before I picked it up and after it respawned.

[WillaWisps]

Same thing with the passed out frog. I can actually pick it up and see there is two in my inventory