Several more attempts and nothing but the same result. Left with no choice but to conclude either something about the US version is causing problems during dumps or my cart itself is flawed/damaged in some way.
edit: while the english translated vpk shouldnt be causing problems, I am going to try the original Chinese vpk of maidumptool and see what happens.
Nope. Still hangs on the manual for a full minute or longer before powering down. Never seen any other game spend that long on the manual screen while dumping so idk what's going on. Maybe my cart is borked?