According to analysis from @buyinsnet shorts are underwater in AMC and deeply underwater in GME. Squeeze prices (the price at which shorts are losing money) are $23.51 for AMC and $16.46 (!) for GME.
Sounds like the GME stock split/dividend has completely destroyed some brokers back-office systems - I keep hearing about the nightmare of dealing with TDA. Also sounds like overseas brokers are having serious problems, and German brokers are struggling getting shares to people.