Was doing some digging on Modelfight, specifically Caroline (last name Yawn I believe) and came across your question. Sorry to "Necro" if if that's considered rude on this board. I don't know a lot about Modelfight but but as you mentioned they, like a lot of smaller companies, have completely disappeared from the internet along with almost any trace or even mention of their videos. I liked some of their models quite a bit including perhaps their best and most experienced girl Caroline. She did a small amount of work outside Modelfight including a few appearances at Fitness Action Wrestling (aka Femmix).
Modelfight was based somewhere in Florida. The girls they brought in were young, fresh and ranged from attractive to gorgeous. Including a young girl named Paula (5'6 110lb) who was franchise material- so gorgeous you can (and should) build your product line around her. Super cute, killer body, great attitude and aggressive. She had it all.
I do not remember a website with restrictive copyright protections. I purchased DVDs from them that I just recently ripped and all went well. Certainly we're talking about the same Modelfight company from around 2004.
I think Modelfight's short if exciting existence is more common than the other example- companies like Double Trouble or DWW whose success goes for decades. I got the feeling Modelfight was started by a pretty young guy(s) and they recruited girls not too much younger than themselves. They lived the dream for a couple of years, blew some money, hit some roadblocks in life (girl friends, got married, got a job out of state, got bored with the work involved running an internet business) and needed to move on. A shame, they did some good, if uneven work. I loved that they worked in a largely untapped market- the south east United States. Tons of amazingly hot beach girls that no one has bothered to hire for wrestling work. These girls do bikini contests commonly, why not ask them to wrestle while in that skimpy bikini? Better money, no drunk crowds.
Fitness Action Wrestling did the same thing and for longer. Sadly they too look to be shutting off the lights. Insanely hot women did videos for them. Most of them professional bikini models and Hooters calendar girls. Southern California is dead for recruiting new talent (lazy companies coasting on their huge back catalogs). Look to Florida and the south east for new companies and new talent.