Pardon for butting in - but I do feel the need to point out that our rules directly point out the matter of game play and story separation. ^^
RPs are, quite frankly, not the games and attempting to adhere to the general plotline of the games and ape them wholesale is generally not only not recommended but in some cases simply impossible. When writing RP posts, you should keep in mind that the games provide a rather simplified view of a living, breathing world with living, breathing Pokemon and events that don't stick to the hand-holdy linear-as-spheres path the games drag you through under the assumption that you are a six year old child with two brain cells at best.
In a setting like this it's safe to assume that Gym Leaders have a good deal of Pokemon beyond what they're portrayed with at a particular time point in the game, in order to take on various tiers of trainers, so to speak. A Gym Leader's job is to be a challenge - but not an unsurmountable challenge - for anyone who faces them. It's rather nonsensical to assume that he'd face every challenger that approaches him with a team of two creatures he just plucked from a nearby route and are proverbially not even out of training pants yet. In the B2/W2 games, you face him as a tier-1 challenge, without any gym badges. Naturally he'd be going easy. Rex here is battling the guy on a far higher tier - not a full on no-holds-barred team (as Ryan has only got two strong mon on hand from his previous run, eight badges or not) but still far higher than what Cheren would send out against an average n00b for whom this is the first gym battle.
It's also safe to assume that Elite Four and Regional Champions wouldn't be a walkover like in the games either, but rather be way above and beyond the pay-grade of the average schmuck. To defeat one Elite Four member is a titanic achievement. To defeat all four of them and a Regional Champion one would have to be beyond overpowered - which honestly is kind of to a scale of godmoding unless the setting is one where everyone is agonizingly overpowered, in which case the Syndrome Axiom takes place and no one is. So yeah, whether or not your personal headcanons of regions feature an animesque league tournament, the ultimate winner of which is considered This Year's Champion and getting a chance to actually face the Elite Four and the Professional Regional Champion (after setting appointments and training your brains out to reach the sort of level you'd need to be to even scratch the surface of one of these people) or whether anyone with sufficient credentials can do so... I'm sure you can probably see why everyone is considering this one person's character's claims about being a 'regional champion' to be empty boasting. They could be very little else.
I know that some of you already know these things and require no further clarification (keep doing you, guys, you make things not entirely dark and dire in moderating the RP boards! ^^) but given some of the things that have been going on here, I felt the need to interject. Hope this makes certain things clearer. ^^