I think the PV can deal with it, but it will not do so cost effectively. You get a PV for mobility, HP and increased penetration compared to the alternative.
Churchill doesn't have extreme armor (240, +6 against OKW PIV) but it has a high HP pool (1400HP), which puts its in an awkward position between choosing either tank (PV or JPIV/Stug). On the contrary, you probably want the PV against the Crocodile/Avre which are 290 armor 1080HP.
In a tank fight 1v1 yeah the panther is fine, but there is probably zero chance of winning in a 2v2, 2 panthers vs a churchill/ff, and it just gets worse the more TDs you stack on it.