Actualy an Hungarian Victory is the PoD how it occurs does't matter,there were in history more battles were the presumed victorie became at last a defeat.
The PoD have to make some sense tough, in order to work. And Louis II's odds clearly didn't favoured him even before the campaign began, let alone the battle itself.
For a "presumed victory" to turn into defeat, you need to find something in the loosing side that could tip up the scales.
Louis II had less men, less political strength, less ressources, less logistics, less technological edge, less everything. Even if, by sheer luck, Suleiman died on battlefield and thatal Ottoman army somehow decided to call it a day (the tactic is otherwise known as "Battle of Endor round-up" and is notable to be essentially practiced by space-opera or fantasy world armies) it would have been at best a tactical stalemate before the next guy in charge in Stambul tries again.
But more seriously, even the death of the sultan wouldn't stop the army : Murad I died at Kosovo, and it didn't prevented Ottoman to score a major victory nevertheless (altough it proved costly, Ottomans simply had more resources there as well).
A must make an apology for my real question is not if they could loose the Battle nut if the Empire vould collapse after a defear.
Most probably not : Ottoman Empire wasn't, since centuries at this point, a dynastical state based mostly on personal leader capacities; but an imperial structure which could easily sruvive dynastical succession. You'd probably see revolts (such as IOTL ones in Central Asia that happened at this time), but nothing existentially threatening.
Who would for instance became the New ruler in the Ottoman Empire?
Sehzade Mustafa, likely. He was still young but already considered as a very competent and skilled person. Barring any "accident", you'll probably see him as a second Suleiman, who would have a minority rule supported by an efficient imperial structure.