I think a castle mod was placed there, maybe called Castle Dumbledore or something like that.
Castle Dunkerlore is located near Deepscorn Hollow (seen on map as linked in OP) as is the DLC Vile Lair, and the larger Reclaiming Sancre Tor. I don't think any of those really affect the central area of the bay shown though, so as long as the mod is not too large in map-space I doubt there would be any conflicts there.
I wouldn't really worry about such conflicts to be honest, beyond those you already happen to know about perhaps.