Surprised to see no zerk or nipple there, but it might be out of sight or on top. Did you check for a hidden set screw?
So it looks like no one here so far, myself included, has any experience with this particular shaft / motor, whatever it might be. Is that gooshy ring around the small end melted plastic and/or out flowing heated grease?
If a propane torch is used (and ONLY if all other possibilities of a mechanical locking method have been ruled out first), and it is determined that the binding is happening on the (I assume aluminum) motor bracket, and not the shaft end pivot, it needs to be applied in two lines, one on each corner, over an arc of around 45degrees of the 90 degree part, or so, to the outside radius of the bracket, fairly quickly, and you WILL char the paint, so have wet rags and a bucket on hand just in case. I see no charring or darkening in the pix, so the heat applied prior might not have been applied in the right place, or not enough of it.
Aluminum expands at a much higher rate than steel, so even if the whole shebang were heated equally, the shaft would loosen some; you have that worst -case scenario working on your behalf. But it's better to heat just the area I mentioned, the idea is to expand that area (and NOT the shaft itself) to release the shaft enough so you can get it out, which is why you need to work fast, and with a helper if you have one.
It's not likely that you will damage the bracket metal with heat; a propane torch is unlikely able to provide enough heat output to damage the aluminum on a massive part like that, which conducts heat away from the area at a very high rate (a quality that makes it difficult to weld).
Looking forward to an answer to this mystery!
