there's a lot of false negatives.. so you can't trust the test if it comes back negative. Best to consider symptoms and exposure.. That's one major problem. the other is that 3-4 weeks of doxy isn't going to do the trick if you;ve had it for a while... you need to use enzymes to help disolve the...
I've been dealing with it for years... It's a job hazard around here. tick awareness is something that is as important as PPE and other safe working practices. I try to avoid serious areas of exposure by staying away from the tall grass and other areas that are sure to have ticks like old...
the fact that you would call them "electric lines" is a good indication that you shouldn't go anywhere near them. Were they service lines to the house or street primaries?
With that level of unawareness, maybe you shouldn't be doing tree work at all. have you thought about a career change????
High Cable is fine by itself... that would extend the trees life indefinitely. Decay will eventually get it, but it may be decades away.
You could add a single rod below the crotch if you want to support the trunk, but the split is already there... there's nothing that's going help it...