When they set off from the Enterprise to Kronos (cringe), they are using a trading vessel "acquiring during the Mudd (assumed spelling) incident". The presence of a Tribble on the Enterprise suggests that they indeed met Mudd who had Tribbles but the encounter went differently (presumably without Klingon involvement).
I wonder if it was filmed and didn't make into the film and it might turn up on the DVD?
If it was filmed (or will be in the future for a flashback) who would you want to play Mudd? Considering the amount of British actors they have, Brian Blessed would be great.