Yes, at the end of the hose there was something molded into the hose itself. I think it was just a really small hole, like it necked down really tiny inside, not a check valve.
But because the factory sender had a 1/2 tube on top that went to the filler neck overflow, I drilled the original vent hole a little larger to accommodate that AN fitting and I’ll now use that as the filler tube over flow. And then use the vent on the Aeromotive unit plumbed to a rollover valve... hope that works.