If you threaten again they may comply but if so it is most likely for the short term. 

They were, however, very eager to threaten foreclosure or encourage a deed-in-lieu.

Now she is threatening us and the other tenants.

Here's my (similar) story: Habitual late payer, usually finds a repair needed, withholds payment, threatens to call codes, has added another tenant to the unit without notification, a HUGE pain in the butt to the neighbors...

During the process, we had to make sure that communication was always open with those people so that they don't feel threatened by us. i used to meet them once in 15 days to explain our concerns why we are doing it.. after first 1-2 meetings, once they understood our situation and realized how professional we were in communicating... things went easy. 

Can one partner's personal mistake threaten the assets of the LLC?

From the sounds of things, since he threatens your ability to find the next tenant, I'd offer him a good amount of money to cut your losses and move on.  

If/when they tell you they need more time tell them that this is not the agreement and that you are filing Monday, if you have already filed what else do you have at your disposal to threaten with. 

I've known this guy for ten years. He's very nice but gets pretty saucy when he's had too much to drink. I manage the property next to his and he doesn't like the renters. Even though they are moving out in two weeks,...

I am being threatened by my HOA board.