I don't have the money to be prop betting, but if i did I would bet on Durr if I coached him 2hrs a day for 30 days in the same match.
I'd take curtains for 50k again without hesitation. You grossly underestimate the time it takes to improve.
Let's put it this way. I wouldn't back myself in a match against someone 300 points lower rated than me, if I started without a pawn, although it might be close. That means it should be even less likely that someone 300 points higher rated than me, should feel confident playing me down a pawn. The reason for this is that small advantages have more value when the ratings of the players involved are higher. Note that no one in the world is ranked more than 350 points higher than me.
So logically I either underestimate my abilities to beat a 2150 FIDE player without a pawn (and I really think I'm an underdog), or there is something seriously wrong with these arguments.
You might be underestimating yourself. I don't have any competitive experience with f-pawn odds, so it's a bit of a guess, but I wouldn't back myself against the best local player (FM, USCF ranging from 2275-2410) and I'm USCF ~2050. I'd play at 2:1 (after some time to work off ring rust).