No, look at Nazi Germany before WW2. It doesn't occupy Poland or even Warsaw. Taking those boarders plus a connection between Prussia and Brandenburg, and... some of Poland is left albeit landlocked.
Odds are he pitches a partition plan to the Russians as per otl and they very well could accept or Poland becomes a battle ground, either way bad for Poland.No, look at Nazi Germany before WW2. It doesn't occupy Poland or even Warsaw. Taking those boarders plus a connection between Prussia and Brandenburg, and... some of Poland is left albeit landlocked.
What I mean is that Nazi Germany Boarders plus Danzig will satisfy Frederick. With Austria behind him, he doesn't need to cooperate with the Russians. If he does, great for him (not for Poland). if he doesn't, then Poland lives another generation... or probably three since the Hapsburgs should try to focus consolidating the southern boarder and their internal issues. Connecting Brandenburg and Prussia makes sense, gobbling up Poland will result in less gains (since your core people are likely to be more obedient and less rabble rousing nationalists than others)