That happened to me before. I drove to work without issue and when I went to go home everything worked except the starter. Or so it seemed. In my case it was a couple of corroded relays/connections in the relay box that's on the frame rail below the driver side headlight. The main relay had pretty much disintegrated. Had to get the box rewired and relays replaced. Cost me about $300.
Pop the cover off of that box and pull out the relays to check their legs.

 

I'll take a look at them. Thanks!

 

You might check the battery too and make sure it isn't low.

 

The CAA tech was feeding the battery 2000amps. He stated if it was the battery then his boost would have solved the issue.

 

Ok, my apologies if I misunderstood.

If the tech saw a current draw of 200A when the key was turned to start (starter control from tipm working and power to the starter), but the starter didn't engage then I'd tend to think it's the starter.

For another test, some here have jumpered the starter control line on the starter to +12 for a moment just to see if the starter will engage.

 

I just posted a video in the comments to try and give a better understanding of what's going on. The CAA tech just brought a pack to boost the battery (thinking it was dead) but the battery seems to be fine and he stated it was the starter.

Not too sure about the other test you mentioned, I'm not too familiar when it comes to engine electronics 😆

 

Heres a link to a video of whats going on...

 

Ok.

It could be the starter, or sometimes the cabling at the starter corrodes and breaks.

If you decide to take a look at the relay box down by the drivers side headlight the vid below will give you a good idea of what to expect:

 

UPDATE: It was in fact the starter motor. The cabling on the starter was completely eroded and turned to dust when I touched it.

Sourced a used starter for $35 and took about two hours to take the old one out and get the new one in!

 

Great to hear, thanks for the update!