I can back that up, as I have a reprint of that story in front of me. Here are Hitler's dying words:
"OWW! The Human Torch has set me afire! But don't let the world know how I died! Tell them I committed suicide! ARGGG!"
Moreover, if you take a look at the letter page (as yet unfilled by letters) of the issue of 'What if?' if question, you will note that they acknowledge that THIS issue of 'What if?' is actually set in the normal MU, as a supplement to the then-current 'Invaders' series. It's in 'What if?' because of the somewhat shaky reasoning that (and I quote) "in the Invaders title itself, the year 1946 will doubtless NEVER HAPPEN!" (Meaning, I suppose, that since the Invaders is intrinsically a WW2 book, a story set AFTER WW2 can't really be considered a part of the series.) Also, to be more succinct, "because it wouldn't fit anywhere else!" So, while it IS in a 'What if?', it's still perfectly in line with regular continuity.