You should still be able to get the customs stamp required from Polish customs upon your departure from Krakow, however you would then have to mail in the forms once you get home. Looking at the website, it looks like the "locally issued forms" restriction is for immediate cash refund only.
Otherwise, you may want to stop by a Global Blue office in Sweden to ask them. It looks like they can issue stamps at the office itself, if they are willing to do so.
From the Sweden page of the Global Blue website:
VAT Refund Information:
Minimum purchase amount: SEK 200.00
Period for obtaining a valid customs stamp: 3 months from the issuing month
Tax Free Form validity: with valid customs stamp 1 year from issuing date
Receipt/Invoice: need to be attached to the Tax Free Form
Customs stamp: an official Swedish or any other EU customs stamp; stamp from Danish, Swedish, Finnish and Norwegian Global Blue offices are also accepted
Passport copy: need to be attached only if the Tax Free Form was validated by Global Blue offices and not by Customs Authorities