OD has played in numerous big $ matches in recent years and according to him, this is how they do it these days. I’m sure it is based on the player’s and possibly even more importantly the backer’s reputation. The fact that JA apparently had none of his own $ on the line should have been a big warning signal to OD that JA was financially struggling.
The way they now promote these big $ matchups on the internet is quite deceiving. They may claim for example it is for $50K, but that’s $25K for each player and the $50K total is most likely the result of up to possibly 10 or more different backers for each player. There’s no telling how much of each player’s own $, if any, is actually bet on the match.