Can't seem to find anyone who has had this problem on GOG or Steam. In the quest Disturbance, when you have to "Find the source of the magical disturbance using the potestaquisitor.", after getting the strongest signal standing next to Ugliest Man Alive, I can't seem to progress in any way. Tried talking to Vesemir, Ugliest Man Alive and Yennefer but I can't see a way to complete this quest. Am I looking in the wrong place?

What you are looking for are some crates of Dimeritium Bombs which are to the left of UMA.

Duh. Thanks for that. Can't believe I missed it though I was quite exhausted when I was stuck so you could say I had a valid reason...