Hello,
I believe that a generation was missed. According to this website (https://www.genealogieonline.nl/stamboom-luser-stasse/I18771.php) Cornelis Jacobz is a son of Jacob Lennaertsz Besemer (1560-1622), who in turn is the son of Leender Jacobsz Bezemer. In short: the current parents of Cornelis Jacobsz should be his grandparents.
Best regards,
Joran
