Despite Dan's financial resources, Doug is pretty well protected from any kind of lawsuit, regarding his allegations/creative editing versus Bilzerian.
This is because:
1) Bilzerian is a public figure, and that can't be disputed. At the very least, he's a limited purpose public figure in poker, but a very strong case could be made that he's a general purpose public figure. This makes winning a defamation lawsuit REALLY hard.
2) Bilzerian has a rich father, has/had a trust fund, and his rich father was convicted of financial crimes. This forms a reasonable basis for suspicions of Dan's funds, and thus cannot be considered baseless allegations.
3) Bilzerian admitted in this podcast that he has "leaned into" the belief that he's playing with family money, in order to get into good private games. This would kill any lawsuit he could file regarding such claims about him.
4) Texas (Polk's location) has anti-SLAPP laws, as do California and Nevada (Bilzerian presumably could only claim residence in either of these states, most likely CA). It is very hard to win a defamation lawsuit in a state with anti-SLAPP laws.
5) Polk, while not as rich as Bilzerian, can easily afford a good attorney to file a successful anti-SLAPP motion to this, which would then get Dan to pay him back. And Dan is collectable.
6) The last thing Bilzerian wants is to have his finances looked into closely, as part of discovery.
Bilzerian hasn't threatened to sue Polk, but I'm just playing "what if".