almothanna

I was surprised to measure 20.7Ω across the two 47Ω burden resistors on the 2013 board I have here. Doing the calculation, that brings the winding to 174Ω. I would have thought that it was a lot lower resistance than that, but it looks like yours is fine. [ Edit: sorry, too lazy to remove the two burden resistors. ]
I don't expect that difference to be a problem, either operationally, or to cause a failure.

It could be excessive bias (measured current at start-up when the current should be zero) from one or more of four current sensors:
output (load) current (there is a current transformer, it looks a bit like an audio transformer) inverter current (an LEM hall effect sensor I believe) output current sharing sensor (might be on the paralleling board? You could try removing that temporarily if you have one) the DC2DC current sensor. I believe that this is something unique to models with the 450 V max MPPTs, so I don't know anything about them. Unless you have an unusual load which has asymmetrical current (hair dryer on half power?), it doesn't look like something you can repair yourself. Perhaps attempt to demagnetise the CT or LEM, but that's about it.
Failing any of the above, it looks like you'll have to get it repaired or replaced under warranty, and I'd say it would be a main-board replacement. This is the most expensive part of the inverter-charger. It sounds like it's brand new (two days of service?), so unless you have any nasty loads, it looks like you should be able to get a warranty replacement. Unfortunately, with high demand and the COVID-19 situation, it may take some time to get resolved.

I would use an old tape recorder head demagnetiser. I have no idea if you can still buy those. Otherwise, fabricate some sort of electromagnet, connect it to low voltage AC (say 3 VAC if possible), and slowly sweep the transformer core, moving towards and away from the core as you go. It's especially important to move away slowly from the core.
It seems highly likely to me that the current transformer secondary is open circuit. The primary should be only a few turns of copper tape, the secondary should have more turns but I suspect it should still have a resistance well under 10 Ω. Unfortunately, if that's the case, it will be very difficult to repair the transformer or to find a replacement.
I think that 12.5 V is just OK; usually regulator chips are ±5%, which would be ±0.6 V. I can't see how any failure of the op-amp could cause the supply rail to increase in voltage. If you're asking whether 24.5 V could be too high for the op-amp, I don't believe so. I'd start with the current transformer. Remove the 47Ω burden resistor first, and measure the resistance of it separately (and the winding resistance; the op-amp will not load it significantly).