As for the game with Padme, it's clear that her counter-hero was Letos (Vitya is considered the strongest counter-hero to Letos), but even that didn't decide the outcome. The last pair, Sinithar-IbBa, was quite even, so it seems like she just had bad luck.
In general, the problem with the first choice could also be solved - if the score is 2-2, you can play a third decisive game blindly on Obsidian. You choose 1 of the 2 remaining heroes, without showing it to your opponent, and then on the count of three, you reveal your hero, and he reveals his, and you play with your chosen heroes.