funny bug and some dude in a cave

[amokay]

so if after you defeat Eric and the undead armies you are placed in the Greenwort castle courtyard at this point I decided to leave via the bridge and go to Grotland cause there's a guy by the name of Ron Rotmouth in an unnamed cave in the SW of the map that has a quest marker on him and I don't know how to trigger it.Obviously he is still not talking to me and when I came back to kick some princely ass I can't get in the castle courtyard, awesome huh?