There are several problems with your setup there, which I've listed below the picture you've provided:
First, the bolt holding the torque arm to the frame would need the lockwasher and washer between it and hte torque arm, *not* between the torque arm and the frame. Otherwise, you could just leave them out and get the same results, as they aren't holding the bolt from loosening (which is their only job). If the item between the lockwasher and the frame is not a washer, but rather the other part of the torque arm, well, you don't need that part, because you've got the important part of the arm already bolted directly to the frame.
BTW, did you modify the axle hole in the torque arm in any way? (it seems odd that the arm would line right up with a bolt hole on the frame with it properly sitting on the axle, and the axle sitting fully into the dropouts...it could happen by random chance, but is unlikely.).
Second, the torque washer is just going to flop around sitting on the axle with nothing to hold it against the frame. However, this doesn't matter because the washer's tab is not inside the dropout flats, so it cannot do it's job. If your dropout is not deep enough for the torque washer's tab to sit *inside* the dropout, you would be better off to turn it around the other way so it can't pry against the frame and try to pull the axle out of the dropout--put it so the tab faces away from the frame, toward the end of the axle.
Third, the torque arm needs to be parallel to (preferably flat against) the frame. If it cannot be made to do so, you must add washers to the axle until they are at least as "high" as the frame protrusion(s) preventing the torque arm from laying flat against the frame, so that the torque arm will be parallel to the frame.
Fourth, the axle nut needs to tighten against hte torque arm's outboard face completely parallel to it, preferably with a thin flat washer between them. If it is not parallel to it, and instead sits at an angle like you have it, the nut doesn't stay in place and doesnt' secure anything.
I'd recommend also showing us the other axle of the motor, so we can help you install the hardware on that side correctly as well.
FWIW, making yourself custom torque plates (with a hole for the axle that is *exactly* the same shape size as the axle, so the axle cannot move within it) to fit within the frame's odd shape around the dropout would give you a more secure setup. Then the plates could be bolted to the frame. You can make such plates out of thick mild steel using a hacksaw and a set of good files, if you have patience and time.
See The Torque Arm Picture Thread for various examples.
