Update: I dropped in a new fan it seems to be working well it turns on with the AC, and I have a working fan control module being sent to me.

I think the problem ultimately was that connection to the positive terminal, I believe over time it probably just got eroded, brittle and maybe the surge coming from the fan / fan control module could have been all it took to finally sever the connection to the battery.

So I guess all is well that ends well CASE CLOSED.

Thank you guys for all your help from the bottom of my R170 heart