Xtol 1+1 at 400 actually makes it look a lot like TXP. You may wish to slow down agitation to every two or three minutes to keep highlights in check. Develop longer to compensate, and thus get back some of the shadow detail you lost.
I have nothing but good things to say of my resulting prints from doing this. Test first. Test first. Test first. If you can. Otherwise use Tri-X in 35mm and do the best you can.

I'm sorry about your predicament. It's a situation where you have to make a choice, I guess. Think about Cartier Bresson shooting Tri-X in 35mm, and the larger prints made from those negs are gorgeous. Also consider Salgado. Same thing. Ralph Gibson. Etc.

- Thomas