Thanks ehBeth, was hoping you'd reply.
My friend plans on arriving in T. on 20th May. One night there and onto Lake Huron with his partner's family for the weekend. Back to T. on 23rd. After that, his schedule is flexible other than ensuring he's in Montreal by Tuesday 2nd June to catch a flight home (to Paddyland, Ceile - he's from County Cork). I would imagine that they would like to spend at least a couple of days in Montreal which may mean passing up on the opportunity to avail of Doors Open.
They're both late-30'ish and relatively sensible so no late-night drinking or such-like. He does like a quiet beer. Musically, he likes all sorts of stuff but leans towards blues-folk. However, if the Vietnamese Boys Choir was giving a recital, he'd probably drop in to investigate. He's adventurous activity-wise and, if it was actually, available would sign up to bungee-jump off the CN Tower. He's culturally-curious I would say and would happily spend an afternoon in a gallery or museum.
Hope that helps.