Deffo damaged and/or repaired imo.
Looks like the bloody sprocket dissolved and fired forwards, taking out a chunk of the swinger. Or maybe the chain snapped and got wedged?
If its been repaired it prolly would have had both arms realigned in the process?
Mine had some snapped-chain damage to it, (now all but 'brushed/polished' out

), and Ive seen ones with the usual ding from the endcan, (it
is rather close fitting on the gearchange side!), but neither showed any creasing.
(My swinger doesnt have the creases anywhere).
To the best of my, (admittedly limited), knowledge; If you bend or crease alloys incorrectly, (ie with brute force/impact), you will get stress fractures forming as the long alloy molecules are over stretched and often break-up.
Did that sound like I knew what I was talking about???
In a nutshell I wouldnt use it.
Just my opinion mind...

Two is the magic number... ;)