Two nights in a row this happened to me. The first night we lost our whm. We decided to keep going. I pulled titan out to help the tank and we made it to the first boss. We actually beat him....and we made it all the way to the demon wall before we got a replacement whm.

Last night, it was the tank. Once again I pulled titan out and we almost made it to the first boss before a tank popped.

I'm not sure the process is the problem. Many tanks do not "join in progress." I don't blame them really. There is a high percentage chance that there is an issue of some sort.

I think there should be an incentive to join in progress.