Luckily I had my Engineers backs when dealing with “Ed’s”. First I would go to his manager and tell them what is happening, along with evidence of what was going on. Then, when the manager ignored it, I would go to our shared manager to inform him of the problem. During this time I would tell my team to push back on it and if the internal client had issues first I would direct him to the service desk manager and then to our shared manager. A little petty at times but usually ended up working since I could lay it out with evidence.