Main cooling fan wiring

Can anyone get me up to speed on this (see the attached).

I am on day 4 of nearly around the clock work on this sub-frame/front end repair job. I don't have the energy to do the research. Why would the control wiring for the main radiator cooling fan be in this condition?

I am assuming that the metal cylinder is an RTD that is part of the 2-speed fan system. Does it control the step-up/step-down relays.

Never had a fire and has coolant always runs well within spec limits.

The big question: Those two leads which lead into the motor - how in the heck are they fused to the winding stabs? I held a good Weller gun - at high heat against one of them (for almost 5 min) and the joint didn't even weaken.

I won't pay for a new fan. Not because the insulation on the external wiring is bad (gone?). So what is proper fix? Insert new leads, butt splices at the terms and heat shrink tubing over all?

Any super genius ideas on this - or just good old-fashioned, past experience? I could use either.