I feel like there’s a lot of information missing here. VLANs operate at OSI layer 2, and Immich connects to its ML server via IP in layer 3. It could talk to a remote server in Ecuador over the Internet, so the layer 2 configuration is irrelevant.
What you have is an issue of routing IP packets between subnets. You just need to set up a rule on your router to allow the Immich server on the Internet-facing IP subnet to connect to the correct port(s) for the ML server on the private subnet. Or maybe use the router’s port-forwarding feature. Lacking further information about the setup, I have to be vague here. In any case, it’s conceptually the same as punching a hole in the firewall to let IP packets from an Immich server in Ecuador get to the ML server on your private subnet, except that the server is not in Ecuador.
Disable the ad block, wait for all of the ads to load so the text stops jumping around like a crack-addled wallaby, accept the cookie notice, try to hit the tiny X to close the inevitable video overlay with shaking fingers, try to hit the tiny X to close the ad overlay, too, decline signing up for email alerts, decide whether to accept notifications, and then read the article one sentence at a time while scrolling past ads.
Maybe your local news sites aren’t as insane as mine?