I'm not sure you are going to get a better answer here than what you got from TI Cycles.
Feasibility depends a little on what you want. One of the issues is the stays will likely have to be spread. There are a couple of threads on here about that. Some people feel comfortable spreading titanium stays, others do not. There is always the chance that one of the stays could buckle. It also depends on what you want as far as dropouts go. They have to fit in the current rear triangle.
Bilenky would probably say they would do it, but I have heard their timeline is pretty long.