@Velma11. It sounds like your guests now have heightened security anxiety (justified or not). I would not have involved Airbnb during their stay on this incident (easy to say in hindsight I know but I have learnt this the hard way).
But yes, I would replace the master (I am the super careful type of host so key changes are a necessity imo. However are you sure that you cant just replace the barrel part for less cost?
Re the lock itself I assume it is a smart lock that can handle multiple codes at the same time frame but that it just got "jammed" . When this happens if you leave it a while it usually clears. Till then I always have a "spare" code (preloaded in app) with unlimited access for emergencies. When no longer needed I can cancel and create another one. If it cant handle multiple codes being used then you need a better lock.
However goes without saying never, ever give out the physical master key to a guest.