However, my PMI is only $39/month, so I'm working toward paying down principal to get rid of it, but it's not exactly an emergency and the profit on the rental more than covers it.Should Thierry do evasive maneuvers to get rid of his PMI?

Then, if he ever causes any issues, remind him that you have a written admission of tax evasion that you're prepared to forward to the IRS...  :-)

Also, wouldn't this fall under the category of tax evasion(as opposed to avoidance)?

This will certainly change the tone of the situation from one where the tenant is either evasive or combative to one where the tenant is engaged in trying to avoid a judgement against them.

Those programs meant to help "trickle down the wealth" has promoted that glorious wage gap we see, tax evasion, financial deregulation, and a free market for our life saving prescription drugs to be so wildly unaffordable here in the States..

He'll have to be more specific about the sources and amounts received from each, and provide proof.If he is evasive, just deny him.

Her response is evasive and inconsistent, which are both flags that she is not dealing with you in good faith. 

At the showing I ask them directly while looking straight in the eye - how's your credit...or anything else they were being evasive about.

In fact you may be falling afoul of gift laws and income tax evasion.

I have brought up several VERY valid, data driven counter point's, comment's and questions and each time you respond with some defensive, uber-evasive BS to run-away from the fact's.