I should probably read the four pages, but I've had this idea for a long time now.
Ben Reily uses the sample, and with further testing it develops into a more stable Humanoid. Eventually, the creature, thinking its Peter Parker, absorbs the life out of Reily to become even more human. He kills many other people until he is pretty much entirely stable as a Peter Parker clone-type. He comes to the High School convinced that the Real Peter is an imposter, and fights him, until he realizes that he is, in fact, the duplicate.
This is where we get the Scarlet Spider, and Ultimate Ben Reily jr. The red symbiote takes on the name of his creator and applies to Bayview as a student, using his shape changing abilities to make himself essentially a Blonde Parker. He takes the name Scarlet Spider (think black symbiote spidey with Red and Black), and tries to take over patrolling the city, which doesn't go over too well with Mr. Parker. Especially when Ben realizes he needs to sustain his humanity by absorbing life.... or perhaps he snaps with the craving for blood and goes insane, and we get Ultimate Maximum Carnage.