A FlyerTalk Posting Legend
Join Date: Sep 2012
Location: SFO
Programs: AC SE MM, BA Gold, SQ Silver, Bonvoy Tit LTG, Hyatt Glob, HH Diamond
Posts: 44,328
Aeroplan can and will force space on AC metal for things like this.
For other airlines, the only "consistent" (and even here it can take some fighting) time I've seen them buy revenue space on other airlines is when they fail to ticket and the space disappears.
I would definitely not expect them to buy a TK flight here, and my advice is to lengthen your trip by one day.
Anything's possible, and I've certainly seen unusual things happen, but expecting them to buy TK J on a date you weren't even booked is just asking for disappointment.