Yeah, prep makes Doom nigh invincible, and poor writing/necessity makes him job to dumb people. Peak Doom doesn't job to any Spiderman. I guess if you want another argument, i can think of multiple ways Doom wins, and none for Vin. Hell, being on Mags' level is justIfication enough. Vin is simply outclassed by the good doctor.
--
The King of GameFAQs Brawl posting from his phone.
http://images4.wikia.nocookie.net/board8/images/8/8b/ViviffChampS1.jpg