Title is self-explanatory, whenever a dispenser tries to place a mob head, the game crashes. Did a fresh install with only quark and the latest version of forge, still happens. Only mob heads crash the game, and everything else seems gets dispensed properly, happens in all directions as well. Mob heads can still be dispensed on players without issue. Something to note is that, after you load the crashed world again, the mob head is placed (although in the wrong direction).

Crash log:
crash-2023-07-14_20.22.46-server.txt