I'd choose calmer sports and outdoor venues before an indoor agility trial. Agility trials can be highly arousing. Dogs running, barking, tugging & growling on the tug (this can be a big trigger!) teeter banging, etc. First, start with outdoor trials. Wayyyyy more space to get distance, turn away, and stay under threshold. Second, what about OB or conformation shows? Confo shows tend to be more lenient about unentered dogs. In both, dogs are calmer than at agility trials. Avoid flyball tournies!!