It will be:
1) Someone already vetted
2) Someone who has demonstrated competence in interviews, pressers and other public venues.
3) Someone loyal and supportive
4) Someone who might help Trump with a voter block
5) Someone perceived to have the gravitas to be President
and Governor Sanders is one of very few that fit that MO.
But it seems far more important to ram a square peg into a round hole as it doesn’t appear as if she has received any consideration at all.