Federal excon can be mail-in voting witness?

Mail-in voting in my state requires a witness signature confirming I received my presidential general election ballot. Can a former federal criminal convict legally sign as my mail-in voting ballot witness? I recall (unless I am mistaken) they can't vote, but the instructions state that "anyone age 18 or older that is not your employer" can be a witness.

 

Thanks very much, @Michael Wechsler and @PayrollHRGuy! I especially appreciate you both including the reference articles for strengthening evidence toward your answers. I think it is likely that Virginia's online ballot tracking is available for my ballot also. I will prefer to have no signature and mail it out asap, and I don't anticipate issues but the tracking is reassuring to make sure things go according to plan.