Wendy's joker messes up Jimbo's awards OR Wendy's joker's description is not full

  This is indeed a major bug. The underlying issue is that the game is supposed to only compare the suit of the replaced card before and after the swap, but instead, it compares the suits of all cards before and after. Since unchanged cards will always have matching 'before and after' suits, this artificially inflates the multiplier. As a result, simply replacing one card per round causes all other cards to receive a multiplier bonus, allowing players to rack up extremely high scores.

  Exploiting this bug makes it trivial to earn the highest rewards. Some players have already created mods that automate 'Joker Card' gameplay using  this flaw. For example, with Wilson, you can farm enough resources in just two days of playing Joker to craft a Rainbow Gem.