We can math it out. He won no less than $8,000 in front games and probably not more than $9,000. His three cars are between $15,000 and $16,000. So at most that puts him at $25,000. If a bonus win averaged $4,000 that means he had to win at least ten of his sixteen tries to get to $66,200, not counting a bailout at some point.
*Eileen Jason took ten wins to get to $39,500 and I don’t remember if she got to fifteen wins, so the rest of the way to $55k had to be bonus wins.
Source, YouTube.
Yes, you could pile up rather a lot of money on Joker’s Wild, but it was a slow boat.