I don't think it's that simple given the timing - the Jays would have had to make room on their 40 man for him, which would mean jettisoning someone else off it. Right now that roster is full, plus they have quite a few arms on the 60 day IL that will require roster juggling if/when they return. It's not that they didn't think Axford could potentially help them at some point in the big leagues, otherwise he wouldn't have gotten so many appearances in AAA over the past few weeks - they likely didn't want to force that roster move without another pitching injury requiring it, particularly right after the trade deadline. For the Brewers, it was still a smart move because it was an opportunity to add a veteran to their 40 man while they are dealing with widespread COVID-related absences to their bullpen. It didn't work out with Axford mowing down the side and it looks like he probably injured himself, but it was worth a shot to the Brewers because it cost literally nothing to try in terms of prospect capital, roster space, and cash (well, 1$).