I don’t know it well but the Salonica campaign was regarded by some contemporaries as one of the worst fronts a British soldier could get sent to, generally because of outbreaks of malaria. I can’t really answer any of your specific questions but certainly don’t be under the impression that things were much better there than in other theatres.

My only source on this campaign right now is Patricia Cara’s ‘A Lab of One’s Own’, about British female scientists and suffragettes in the war. There’s not much in there about it, but it does pop up since a number of women were sent to establish hospitals in Serbia and then later in the Salonica front