Hello,
When looking at the pictures posted I first thought they had put some avalanche protection diodes across the output
of the rectifiers but after enlarging the picture and putting my glasses on I can now see that they have paralleled the
outputs of the rectifiers, possibly via two low value resistors? I have not seen this done before, I imagine it's maybe
done to share the current as one rectifier is rated at 1 amp and the other is rated at 4 amps so maybe the one rectifier
was a bit borderline. Or maybe they need to share the reservoir capacitance, it's not clear
I don't see why it needs two rectifiers anyway, it obviously didn't work very well if they had to strap them together
after manufacture.
If that board burn between C653 and the link wire is a piece of track blown out then it's possible that IC67 has failed.