I'd never ever team up with anyone below full Columi in HM Lost Island. Columi geared person needs to be a good player too. If he/she is an average player I'd rather go with Rakata/columi.
Sorry but this part just gets me. That's absurd.
My first run through Lost Island ( as a Sentinel) I was probably 50/50 Columi and recruit mk-2 gear. It was an interesting run because half of the group of 4 was there for the very first time, but damned if we didn't finish the whole thing. And NO it was not a zerg fest with deaths every few encounters and NO the 2 people with experience were not uber geared to carry the other 2 through. What those 2 experienced people DID have was patience and a willingness to explain the encounters and offer suggestions on how best to overcome them. More people could benefit from that kind of attitude.
Lost Island isn't as hard as people make it out to be. It's almost completely about coordination and working together and after someone sees how an encounter goes and the entire team puts forth a moderate amount of effort to work together instead of arguing and pointing fingers it becomes... rather easy.
Heck, before I started collecting Rakata I was complimented more than once on my DPS performance on LI and no I do not think it's because I am an Uber player. I hold no illusions about that, I am an average player or above average at best. I just put in effort to adapt my play style to my team and pay attention to what needs to be done.
As for someone looking to run LI for the first time I would probably suggest half columi at the minimum and by that time you should probably be sporting a few BH items bought with comms. If you are a tank, you'd want to be geared slightly better.