Louie can't stand my office door being closed - HELP

I think my cat Louie has separation anxiety. I have a job where I work at home, and I have accordion doors to close off my office so my kitties can't come in and "help" when I'm working. Of all 8 of them, only Louie seems to have an issue with this. He stands on the other side of the doors and cries, meows, scratches, drags toys over and generally makes a lot of noise for literally hours on end. Part of my job is video phone call related, and he is so loud I'm afraid the people on the other end of the phone will hear him!

I could shut him in my bedroom, but for an 8 hour shift that seems like a punishment he doesn't deserve. I know he wants to come in, and whenever I get a break I go out and love him. He has toys, cozy places to sleep, food, water, clean litter, windows to look out of and 7 companions he can bother, but nothing seems to entice him away from the office.

Please, does anyone have any advice on how to get him to accept that mama needs to be in the office alone and he doesn't need to stand there and cry? He breaks my heart and I don't want him to feel punished, but I can't lose my job because my cat won't shut up!

Thanks~

8whiskers, catmama to Autumn, Duck, Louie, Luna, Peanut, Shyla, Turtle and The Wee One.

I would love to be able to let him (and the others) into the office while I'm working. Unfortunately, I can't. I am on video conference calls when I work, and Louie has a terrible habit of jumping up on my desk in front of the monitor whenever I'm in the office. I can't have cats on the video call! :-) I was on a call once and didn't realize one of my kitties was in the office with me, and she jumped up and the client saw her. My boss called me later that day and said I couldn't have cats where the clients could see them, so they aren't allowed in the office. If video wasn't involved, it wouldn't be an issue.

So, since the most obvious and the best solution isn't available, any other suggestions?

Unfortunately I rent, so I'm not allowed to make any structural changes. The office only has an open walkway, no actual door, so I put up the accordion doors to at least keep them out. the ceiling is vaulted, so they don't go all the way up. It's the best I could do. I just don't know why he is the only one that has a problem with not being able to come in to the office. During my break I keep the doors open so he can come in, and whenever I'm not working they have free reign. He's quiet except for when I'm on one side of the door and he's on the other. He sounds so pitiful he just breaks my heart!