RBR850 satellites won’t connect

So I bought a used RBS850 to add to my existing two satellite system and after much frigging around two days later I have no satellites connecting any more…doh!

I’ve tried all the standard stuff except resetting the router. I’ve “factory reset” each satellite multiple times (which doesn’t even seem to reset the name of the satellite?) and, yes, I’ve tried starting with wireless syncing. Is it really time to bite the bullet and reset the router?