Well, I've been pretty busy because in between losing my job last summer ("Covid budget cuts") and getting a new job (more money, so up yours old job!), I started a pretty big yard remodel that I'm now having to finish whilst holding down a job too. I thank you all for your suggestions which I am working through. I snatched MLK day 1hr slot I have investigated the Charcoal canister, because its easy to get to!
Conclusion is , it seems good. Everything looks in good shape. Those two center ports both held a vacuum. The bottom one you can see in the gauge seems OK, the vacuum dropped very slowly but when I reconfigured the hoses to my gauge dropped even slower so I think one of the pipes was the leak. Both passed the "tongue test" with no sign of unsticking. I can't see a case here for dropped over $100 on a new one