L,

Your MC isn't going to tell you if he thinks your M can be saved after just one session with you.

I'm inclined to believe it's because he would like to see you some more before he makes up his mind how often he feels he needs to see you.

Look at the other side. Maybe he feels he won't have to see you as often as once a week because he has an inkling that it won't take that much to get your M back on track.

As far as your second question. Do you know if this MC is well versed in MLC?

All you can do is ask the MC. He'll let you know if he doesn't think it's a good idea to see you alone. Do you think your H would have a problem with it and worry that you'd have a 'one up' with the MC if you saw him solo?