Yes - I ended up doing similar in my bathroom and it's been great. I did have a plumber do it and your cost estimate is good.

It's incredibly hard to earn a living in the arts. The coworker was trying to stir up some trouble by suggesting I was on the verge of quitting.

Then there are some who would use anything as a way to get an advantage - for that coworker it would not have been impossible to have the conversation go something like this: "oh, well MET1 wants to quit and become a painter so can I get some training to take over that position". See how that works?

He was a jerk.

I tested a co-worker once - I told them that when I have vacation time I like to sit in the park and paint. Not something I have done and never told anyone else. A few weeks later my director mentioned something about how I could not rely on sitting in the park and painting as an occupation. Lesson learned.

Adhesive backed cork squares - available at office supply stores might be an easy, more attractive option.