Roku integration not finding all Roku TVs

I have three TCL Roku TVs. I have added the Integration to my config.yaml file like this:

  - host
  - host
  - host

It finds the first one just fine. It cannot find any others. These TVs are on VLAN12 of my main network, with bridges allowing the main network (br0) to communicate with the Media bridge (br3) via iptables and DD-WRT.
All my computers / phones can find the Rokus just fine, so the networks routes are valid and working.

The main network is on 192.168.50.x, including my HA RPi4, which is also configured with VLAN12 on the main Ethernet port.

So question is, why can HA not find the other two televisions? Is there any other way to manually add them via the Roku Integration? It seems to only allow manually entering the IP address for the first device, then there is no option to manually add more.

EDIT: I should also mention that my Plex server is also on the 10.2.0.x network, and HA finds it just fine.

Thanks in advance.