Hi. Until now, this profile had not been adopted into the New Netherland project. I changed that, as it's clearly in scope for New Netherland.
Reading the profile and checking the sources there, I don't see conflicts between sources. The various sources are 19th- and early 20th-century books, which aren't exactly ideal (they don't qualify as reliable sources for pre-1700 profiles), but for this family they are what we have...
What I see in the profile is that several books identify this man (born 1687 on Staten Island) as a son of Daniel Stillwell and Mary Mott. And there are a couple of other books that indicate that a Daniel Stillwell, son of Nicholas, was born in 1696 on Staten Island. He can be assumed to be a different person. It was very common for New Netherland families to include several male cousins with the same first and last name. Since the sources agree, I think it's reasonable to say that the man born in 1687 was the child of Daniel Stillwell and Mary Mott, but I wouldn't mark that "certain" because the sources are weak.
Things get interesting when the wives come in. The WikiTree profile gives this man born in 1687 two wives, Mary Poillon and Catharine Larzalaer, but the sources seem to give these two women different husbands, both named Daniel Stillwell. Teunis Bergen says that the man born in 1696 married Mary Poillon. And Dewitt Stillwell says that the man born in 1637 married Catharine Larzalaer. Neither of these sources assigned both wives to the man born in 1687.
So, what is the evidence that one man married both wives , and what is the evidence that the man who married those wives is the son of Daniel Stillwell and Mary Mott who was born in 1687? It's chronologically possible that they were the same man, but the fact that it's possible doesn't make it "certain." The necessary evidence could come from wills and deeds (I've not dug into those), but sometimes it isn't possible to determine which of two cousins of the same name had a particular marriage or children. Unless and until there is a convincing basis for answering that question, I don't believe you can mark anything on this profile as "certain."