I don’t know your specific coworkers, so this is my experience:

He/they can be a reasonable placeholder for not wanting to confuse non-queer folks with any/all which doesn’t have a great shorthand. He/they gets close enough, especially for something that I don’t have strong feelings about.

There’s also maybe an argument for putting they if you’re ok with it. I had a trans coworker who very much was not ok with people calling her they.