I just don't think he can actually play OF (well, or at all - only 14 games last year, 58 the year before). And I don't think what he did last year is likely to be repeated.
Plus he's not really available. And he'd never play with Crawford because Crawford would be on the A's (and so would two more decent prospects).
Not to mention the Phillies already have a LF now. If Kepler flops and Rooker is available at the deadline, sure, he's on the list. Ditto if Castellanos flops and the Phillies were actually willing to do something about it. Or if, God forbid, our DH or 1B had major injuries. But right now there's no place for him on the Phillies roster.