When tenants choose to 'not behave' according to their contract, you should always try to remedy the situation by holding them accountable and then, if the still choose not to cooperate, find a creative way to 'encourage' them to move out and leave the house in good condition, without putting yourself at the mercy of judges and lawyers. 

I will also be getting lender credits and realtor credits so I may be having a log of money left over at closing.

The guy isn't really concerned about the money in the offer, however, he's attached to this house he grew up in and seems to be having trouble letting go.

That could be enough to spook him into behaving.

For some reason it seems that we can not because it is a closer than arms length transaction...I might just be having a mental mix-up :)

One of my friends suggested I may be having issues because I am a woman,  I would like to think that this is not the case.

Actually, people that behave like that are forcefully reminded that they reflect on us all, and if they continue, their affiliation can and does get rescinded.Mentorship within this group is excessively generous, and without expectation of reciprocation.  

And because the tenants do not want to lose their Section 8 status, they tend to very well behaved when it comes to their share of the rent and any standard tenant issues.

As others have stated, this is not your business.What would you do if your neighbor were behaving the same way?

Another alternative (even if it's kind of a pain) might be to write them a check out of your personal account and then expense it back to the LLC.I'm not a lawyer, but to me that seems like it may be enough to not be commingling of funds, since the LLC is still behaving like its own entity?