If you're looking for other stuff in the slasher jam, click in the top right corner where it says "submission to slasher jam" and that'll take you to the jam page. Then just re-click on the submissions tab.
As for using this with Slasher Victims by Michael Mars, Splatterborg isn't meant as a replacement for Slasher Victims. Slasher Victims is in its own setting, and Splatterborg is in the Dying World. I like Slasher Victims a bunch, and didn't want to step on its toes.
That said, it should be possible to mix and match Slasher Victims content with Splatterborg with a bit of conversion. In particular, the Stalking Murderers in Splatter should be droppable into Victims without too much tailoring.