If stroke play is to be the deciding factor, it makes more sense to have single player rounds on a WGT designed custom course, with groups organized by tier and playing from tier default tees regardless of the credit ante. Those who bet more and play higher divisions would win higher level balls, more packs, etc.
If head-to-head is the goal, keep the coin rooms as is but make it a match play format with total score functioning as the ranking/tiebreaker between players with equal number of match wins throughout the round. Put the onus on winning the match, not just playing for the score.