Is there any reason to assume that the over current is not tied to an unrelated issue? An intermittent failure with a cap or other component causing a short somewhere? I suppose you would need to schematics to see where a short between 5v lines would cause that.
Or would be due to the failure of the reset mechanism in the chip causing the excess current draw.
The overcurrent could very well be unreleated to the reset issue, but it's most likely they were both caused by the fault.
The most likely scenario we have evidence for so far is that something took out some aspect of the reset circuit. Might have been the failed 5V rail cap failing causing over voltage.
SCR latchup is a strong possibility. Once again, might not be, but you won't know unless you spend more time tracing the circuit and troubleshooting. Could be many many hours of dicking around, only to eventually come to the conclusion that it probably is SCR latchup. or you could hit a winner, but you don't know unless you put the hours into it.
It's unlikely you'd get another programmed chip, and you wouldn't risk putting back into a service a device with potential SCR latchup issues.
This one is just way too big of gamble.
And some people have complained that I didn't fix it and I wasn't creative enough etc.
At some point in cases like this it comes down to how bad you want/need to repair it.
Well, for me, this is not my fight, I don't care enough to trace it further, and I have a strong hunch it's SCR latchup. That's good enough for me to call it quits on this one knowing the odds of success from this point on.
I'm very confident I'm not going to crack it with another 30 minutes of work.
It is highly likely this thing is screwed and I will have wasted a lot of time for nothing.