No. Well, you can but keep in mind that it could affect any severance that you are intitled to. I've heard of employees getting surplussed while on FMLA for medical or maternity. Stankey badger don't care.
Suppose that you have a contract that stated you are entitled to 18 months of guaranteed employment upon relocating. That is contingent upon performance. You don't perform, you don't get paid. It is also contingent upon business need. New mom's frequently lose the cherry gig they had because, well, they left. Company has to give you a job, you don't have to like it. However, if they subjectively decide that you aren't capable of performing another job, you may be surplussed. Sure, you can object, but you have to then refuse any package they offer.
Now, pretend all this happens. You have a case, it goes to trial a year down the road. You've since landed a good paying job in the DFWM. Similar salary, similar benefits, good WLB, short commute. Judgement to the plaintiff, whatever your severance would have been, if you're lucky. If you happen to land a better paying gig, judge might dismiss and tell everyone to go home. You and your attorney can discuss the legal fees that AT&T won't be paying.
Anyway, that's about how these things work. unless you can prove you were discriminated against, you're in for an expensive journey. Heck, even if you were discriminated against. A lot of judges are tired of being in the middle of a battle over hurt feelings. So, cut your losses. Texas is an OK place to live for a bit.