As you are “an IT Guy”, i recommend you read below, and try to imagine what you would prefer seeing/hearing from people, try to troubleshoot their devices/network, in specific as you certainly don’t seems to have a “standard/basic” network
How to help us help you - or How to ask a good question.
PS: Remove your second “Router” from your “Setup”. run cams on your local (1 network/1 Router) … it’s basic trouble shooting … Sorry, can’t hold your hand, or “push” your further, or give more " throw in the dark, guessing" suggestions.
Thou im still thinking , You got 3, which all seems fine ( yeah i know same Brands … VolksWagon also make Porsche ) , stick to the 3 , and use the other 2 for something, or start from scratch, to see if you have ANY chance to get the 2 “Others” to play along
Then use Frigate.Card in HA, Or is your “Frigate”, actually a standalone Installation ? …