Just out of curiosity... why does your landlord think that your H would start a second family if you don't renew your lease? Just asking...
As far as his inner turmoil goes... I've read that could be a sign that he's finally beginning to work things out in himself. Possibly a good sign... also a point where he could go into the MLC "replay"... nothing you can do to prevent it if that's what happens...
Best you can do is let him work it through. I guess you can validate if he contacts you. I've heard that any questions from WAS regarding R would best be responded with something like, "I am not sure what the future holds" or similar...
As far as the R between your parents and your H... *shrug*... IDK...
It is a difficult enough road to rebuild a M as far as I've heard. I'm guessing that rebuilding all the Rs that are interlinked to the M would have their own challenges... Likely part of why it's said that rebuilding a M is possibly more difficult than having to deal with a possible D...