I remember trying to get Atma when I realized I was doing it with a full inventory, meaning even if it did drop, I wouldn't know because my inventory was full.

Funnily enough, the next fate I did after trimming my inventory out yielded Atma.

But yeah, if a bug does happen where you can't get Atma, it would be a nightmare, especially since people would think the RNG just hates them (which it usually does)