I might just still be too tired from just waking up, but I can’t for the life of me find any details on that site about what models are actually being served by the horde?
Go to https://aihorde.net/api/, scroll down to /v2/status/models, and click Try it out and then Execute. It's an enormous list and I think it can be dynamically updated, so that's probably why it isn't listed on the website.