The interesting thing with Ratmir is, that every time you talked to him in a quest-related way (
Plundered Stylist (PS),
Luxury Outfit &
Royal Robber), new monster-stacks are on the map in Riftland. These stacks are concentrated on the area around the lighthouse.
As far as I figured out, there are 5-6 Areas, where new stacks (regarding the
Plundered Stylist-Quest, these are
always Viking-Stacks!) appear, as long, as the ones that are present there right from the start, when you first enter Riftland, have been defeated. Two of them are located on small shore-areas near the lighthouse. And it's the same for one chest in the sea and a tree stump. Both locations are also in the area next to the lighthouse. I'm not sure if you have to dig for one of the stashes, but if so, this hidden chest will not be available before you had the first PS-conversation with Ratmir.
So, in my last walkthrough, I first eleminated every enemy-stack around the lighthouse area, searched the area for treasures and plundered all hidings & the chests in the sea, before I talked to Ratmir for the first time. And it worked out perfectly, because you are then able to see where the stashes are located, as there are new enemy stacks a new marked hiding and a new marked chest in the sea on the minimap.
Maybe this helps those who have problems with the quest, as it is quite unusual for KB, that there is a kind of enemy-respawn on a map where you actually are and maybe there is a problem with the quest, if there is an overlap of the stacks/hidings/chests.
BR
J.B.