You don't have to be a coach/official (or player) to be in the dugout. You just have to be listed as an occupant with the match officials before the game. The only rules that determine occupation relates to the number of people allowed and this varies by competition.
Our dugout at Hibs included a groundsman and kitman.
As I understand it, Foran won't be allowed in the dugout, but that is entirely due to his suspension...he will also be restricted on when he is allowed in the tunnel, dressing room or allowed to sit in the direct vicinity of the technical area (something that the official missed with Kenny Shiels when he sat behind the away dugout when sent to the stand at our place).