I can confirm that's how it worked on my 9 passenger wagon. With the gate closed, you could reach up inside the wheelwell and get to the clevis pins. They did not retract thru that baffle hole...I believe, but I'm not absolutely sure, that based on this the wagon cable clevis doesn't have to go through the baffle hole.
And I don't remember seeing a rubber grommet. It may have been long gone from 50 years of use though...