I just read a post from F.EM.A that claims that even if you have the companion glitch (you go to northern passage, ask Jed Masterson to take you to new zion, and he says your party isn't empty even though it appears to you that it is, seems to usually be related to ED-E) you can start HH by simply walking to the end of the tunnel in the northern passage and a dialogue will come up saying "Enter Zion" or somehting like that. According to F.EM.A if you do this, you will begin HH as normal.

I don't know if this will bring ED-E back into the game, if it empties your party, or if it just allows you to play HH. Or maybe it doesnt work at all. Are any of you able to test this out? I will test it tonight, but I'm really eager to know if this works!

So anyone able to try and report back?

Tried this last night. Doesn't work.

When you go up to the end of the tunnel, there is an exit that says "exit to New Zion" or something similar. When you hit a on the exit, a message comes up saying something like "You must travel with the Happy Trails Caravan on your first visit to New Zion".

So unfortunately, this is not a workaround, as it does not allow you to play HH if you are experiencing the companion glitch.

Still waiting for that patch!