Did you clear computer? Ican see it throwing a bunch of codes with the voltage/amperage so low. Also I'm not sure if you had 13.5v@ the alternator while still having the low batt voltage,it should be 14.5 @the alt& batt with the grid heater off.I've seen the output post of the alt get all arced where it connects inside thus reducing output. Check ALL connections from batt,grounds,power distribution box alt to Both batterys,load test batterys.
OOps! forgot to mention after fixing canister leak,check/replace fuel filter,check lift pump pressure