With full knowledge of Polish internal and external situation I would choose option 3, but with some modifications:

1. Mutual help, but rather in the form of money for Poland - imperial tropps usually caused more problems than they solved and their forces marching through Poland would cause some anti-Hapsburg feelings, especially if you consider the appaling lack of discipline at that time.
In return some form of Polish 'mercenary legion' would be a good option - in similar way to 1680s when before the official Polish army arrived Lubomirski's mercenary troops were already engaged.

2. Poland is already at war vs. Sweden and there is a growing tension with Russia and the Ottomans. For this reason money would be good as soon as possible to prolong the conflict with Sweden.

3. Some diplomatic efforts in fending off French diplomacy trying to mediate and to encourage Swedes to invade Germany is required. Countering French efforts is required the most.

Of course if I can propose something like this.

Regards Cegorach