Then take a deep breath, stop over thinking it and build rapport with a model before you purchase something like a custom video.
The model you purchased from doesn't even care enough about her work to do a single thing with her profile, that alone should tell you something.
@Bobby3975 take this advice, keep in mind this is your recreational spending: Take the fun out of it and what is the point.
I have been ripped off and banned a few times (9 years MFC/ 180 000), had the same no response from support that you did. Also considered the switch to a pvt based site quite a few times because of it. The only time I have had help from support was when I had login trouble, they were super helpful then, multiple replies within a few hours.
Forget about the ban, it was used as a form of cowardice; she was just running away from confronting you or your reaction.
If you feel like guesting (looking at her stream as a guest) go for it, take as much guilt free pleasure from it as you like, ripping you off gives you guilt free perve privileges until you feel compensated.
Look at her room background, profile, and MFC suggested models, she may be a studio model. Use extreme caution around any of her 'friends' if you seek someone new, especially for a custom video. [This is one of the more nasty things to members that MFC does, it can lead you to more models with an intent to rip the member off]
I would highly recommend that you look for models who sell videos on a regular basis for a custom, and buy a generic one first. Customs take a long amount of time and energy to produce, so be suspicious of anyone selling one cheaply.
On revenge or getting your money back, I'd personally take the learning experience and move on. You won't be as much fun or as free with your spending for future models, but that is the price the community pays every time this happens.
Risky models can be a lot of fun; you can get really good one on one attention, so they do have their role on any site, but be cautious with how you spend and expect to take the occasional loss.