At this time, I don't want to miss this opportunity should I make offer directly with this listing agent to get highest chance of accepting offer or talk to my own buyer agent (which she doesn't know this off-market deal, and I don't want she to spread the word to other interest buyer and increase my competition) and see if she can help me with submitting offer? 

For instance if they miss payments, or don't pay the taxes, or let the insurance lapse...Vic

I went to the page and they are missing a lot of details such as what the 'closing the fixed- term lease loophole' actually means.  

I’m a project manager full time and a general contractor/handyman on the side, I have zero issue putting in hard work but I do have an issue missing out on time with my kids.

@George White, you won't be able to remove the mom in this situation if she does not want to go - at least not until she has missed the rent payments.

Aside from resale which I don't plan on doing for many years, what other aspects am I missing?

James, again, you are missing the point. 

While your at it, ask that lawyer for the missing section of your lease and have them review it immediately for other shortcomings.  

I think this calls for a drink (or more). 

I am told that NOT doing it and i miss out on VA etc buyers.