2015 Tahoe with stabilitrak issues and weak battery

[TennesseeMomma]

Even before replacing the transmission. The truck would drive horribly when the stabilitrak light would come on. After replacing the trans, now the engine light flashes and the stabilitrak light is stuck on the dash. Battery falls weak or fluctuates charging, and the truck will shut off when disconnecting while running. Throwing P0202 and P0208 codes now, but no change with new coil pack on both cylinders, and no wiring issues have been found. Surely, almost 10 yrs later, there is a resolve. Save me from this horrible model year..