In the bio it says "His mother had been a Pomeranian lady whose '''first name and precise origin is not known''' to us, but who is indicated to have come from the ducal family of Pomerelia." Wouldn't it be better if his mothers profile, Hedvig Svantepolks de Gdańsk, of Danzig, reflects this? If there isn't any sources that supports who the unknown mother's parents are, we should remove her parents and let the tree reflect what the sources says. On the other hand, if there are sources that supports that Svantepolks grandfather is Swietopelk II, Duke of Pomerania, we need to change Svantepolks bio to make it less contradictory.
Just ignore that part in his bio, read https://finnholbek.dk/getperson.php?personID=I3060&tree=2 to see the relationships.
Unfortunately, that information you refereed to comes from the Swedish ÄSF, and from one single individual.
Swedish so called experts have often been bad or unwilling to accept other foreign experts conclusions, like for example from the Denmark's Nobility Yearbook.
Swedish experts in this genre of genealogy rarely accepts just one or two evidence, but have required at least three proofs, and unfortunately sometimes still questions the result and conclusions that can be made thereof. So with much higher requirements to accept evidence than most if not all other, it often leads into pure crap and big confusion.
Feel free to adjust the info in Svantepolk's bio so it's in accordance with the reality of other peoples conclusions and result, not from just one single Swedish genealogist.