Have you inspected the connectors like I said earlier? Have you taken pics? We are getting to a point where you have to start supplying visual input to get better advice.
If your board edges look like this:
And your connectors look like this:
Then you will have tons of issues and your switch matrix can go nuts.
Personally, testing the spider chips is a waste of time. There is a list of things you can check that will pretty much tell you if you have a fried spider chip or two. With a scope, it takes like 5 minutes to figure that out. The guide then goes into a detailed check of the spider chips, but why? You can't reasonably replace them.
You can test the board by soldering an led and resistor across the inputs of the top/right most display chip, and then connecting only the top left power connector to the board. That will take all of the connectors out of the equation. That procedure is outlined in the repair guide. If the led comes on after 5 seconds, you have a booting board and know the hanging problem is in the connectors.
And yes, you really do need to bite the bullet and repin the connectors. It is a royal pain in the ass to get started, but gets easier as you go. Proper tools are an absolute requirement.