Maybe a side effect of the last stand updates. Maybe servers and mods need updating like with any other game update.

for the record, Yama had issues long before the Last Stand update... though i'm not aware of any from the update. originally there were only some finale issues which "RF" fixed, and then he fixed up some other problems afterwards. this simply combines everything (all of the separate workshop "parts" into a single VPK). thus also keeping a current version available here for those who don't use the workshop. original author seems to have mysteriously vanished, neither me nor "RF" could reach him, so we took it upon ourselves. "RF" was granted permission from the original author (you'd see he was credited and made a contributor on the workshop items, or was). he's also fine with me keeping this alternate mirror available here. and yes, I also have my own thoughts and opinions on the whole "team" for the update, however i'll refrain. there's enough drama from it as it is, I could even call out and expose some things, like how they brainwashed higher ups to keep me out. but yea, after hearing how various people got removed or quit from their own choosing, seems I'm better off without in the end. I don't really care, as with any and all Valve content, it's now freely available to mod and so I'll be modifying Last Stand eventually. but it'll be done right, unlike the half ass attempts from a certain thieving someone else lol.

It greatly amuses me every time they ban me from Steam forum and say "banned for posting false and fictitious information", and I'm like: - update broke a gazillion of mods = TRUE - Last Stand "campaign" sucks ass = TRUE - noone wanted or asked for this crap = TRUE - Rayman and the rest of the team suck = TRUE. As a L4D2 community original, I know exactly what I'm talking about.

check the change log, it has the official and approved fixes from "RF" also known as "Recycle Bin". he had the blessings and support of the original author, unlike Huck and a few other random users. so this is basically just a proper fixed version you can trust. also serves as an alternate download for those who don't use the workshop. there might be plenty of people already using the same fix off the workshop as the Yama author does link to it.

I also forgot to notice if you kept the version at the original last known 6 from Surgeon or if you changed it. I think you kept it the same and only did fixes and changes that were necessary so it should be the same here as your fix. I only made sure to change the add on info and missions text files to point to the original workshop collection for everyone.