What were the results of your electrical diagnosis?
The goal is to ensure 12v is present at the blower connector, and something is clearly currently preventing this.

Here's what I would do if I had your symptoms:

Turn the ignition and blower on.
To diagnose you generally start at the fusebox (blower fuse) measuring whether it has 12v, and then work logically towards the blower:
i.e. Fusebox -> switch -> resistor -> thermal fuse -> blower

At some point you will lose your 12v.
The trick is to first isolate the problem, then understand the cause, then fix it.