As long as it's just out of alignment by a couple millimeters you can probably fix it as suggested.

The bending that's already occurred and what you will do to fix it has and will leave micro-cracks in the alloy. However, while the piece will be weakened by the process it will probably hold up just fine afterwards given how the somewhat only moderate loads that the timing rings handle is distributed around the five arms.

FWIW: I've straightened a few aluminum derailleur hangers in my days and some other cold forged and CNC'd parts to no ill effect. It it was cast aluminum it might be a different story.

Bottom Line: The alternative to fixing it is probably replacement, yes? If so, what do you have to loose? Heck, even if it did shear-off I suspect you could probably still ride your tandem with the other 4 arms supporting the chain ring until you could find a replacement.