2008 - Not Starting, No Lights

I would suggest something does not add up. After shorting the battery posts with a wrench was there a failed jump start attempt? A reversed polarity jump start would blow fuses or fusible links at minimum.

I can understand the 12v battery failing from the direct short but not the inverter. It's more likely other fuses or fusible links are blown.

I would probably check all fuses one by one ensuring they are all good and none are in the wrong slot. Most likely I would reinstall the original inverter as well.