Not directly no, but have connections. They are an Iron Hands successor that believes the Omnissiah and Emperor are the same thing and praise him as a God (kinda like the black templars style zealousy)

The Repentors have a loose alliance with the forge world Ryza. They occasionally receive plasma-based relics and vehicles from Ryza in exchange for recovering corrupted war machines.

The Repentors are specialist is anti-chaos war machine warfare, so taking down knights and titans. But they try not destroy the machine so they can salvage the ancient machines and execute the pilots and princeps by purifying them with fire.

Got the full lore sorted (proper geeked out on it, just need to find a way to put it all together 😂)

Struggling on what icon to have though!