The Catholic church stopped selling indulgences for cash in 1567, 322 years before Hitlers birth. There were still a number of other totally arbitrary ways for him to obtain indulgences such as “devoutly” carrying/wearing specific items, celebrating certain feast days, etc... However he would have had to reconcile his Mortal Sins to avoid Hell before worrying about reducing his time in Purgatory via indulgences. All that non-withstanding, suicide is a Mortal Sin in & of itself which can’t by definition be reconciled prior to death, so he would still find himself in Hell for that alone according to Catholic doctrine.

I’m an Agnostic who was raised Catholic, maybe “culturally Catholic” depending of definition. My point isn’t to defend Catholic theology, insomuch as highlight its relative complexity when compared with the Prots. I would agree its all very stupid. The Catholic Church just adds more convoluted rules.