Maybe if you run into said "promissory jerks" at an upcoming event, you can let them know in person that you are disappointed in their follow-through.
otoh, jerks are not often found at our community events. An exception or two have managed to slide through the gate on occasion; which gives me the opportunity to "educamate" them a bit. Indeed, has happened that a lady or two has gotten a look at some mugs and reported multiple handle issues.
Stuff happens, and you may be better off to let the ladies who vouched for said fellows about the issues.