I had a battery ark on my charger pigtail
That is really strange because generally the Tender charger pigtails are directly connected to the battery posts (with a fuse). If you short out the pigtail charger lead to frame ground (even if there is no pigtail fuse), it will not open a circuit breaker that is downstream of the battery.
Where does your Tender charger pigtail hook to. It must not be directly to the battery.(?)