This is one of mine from a month or so ago. I have used a tree, log, rock, etc. to temporarily fix a wheel to limp back to the car. Most stuff this bad will NOT fix by spoke tension alone. I personally will not trust any rim 'brought back' by bending, you have fatigued the metal by doing so (was already fatigued once by whatever mishap had occurred), and aluminum does not fatigue well at all. I would replace the wheel or rebuild with new rim/spokes/nipples.