Legal question - slightly but not really off-topic

First, apologies for posting this here, but I know there are a lot of very knowledgeable people here, and this isn't really all that far off-topic....

I have a friend who rents out a residential piece of property in NY to a (shady) guy; he's currently the subject of several major lawsuits, both shareholder and liability suits. He has a history of paying his rent by check from a corporate entity; recently, after the filing of a new suit, he dissolved one of these entities and created a new C-corp entity, which now pays his rent. There's no written lease / rental agreement; they had one, but it ran out years ago and the owner was told that in NY she is better off without a written lease.

The tenant has two cars, and recently they alternately disappeared for a few weeks each; he said they were in accidents, but there was no evidence (both came back dirty). I know that one of the cars was actually owned by one of his entities, an entity where he is subject to a large shareholder suit. (And I indirectly have a not-insignificant shareholder interest in said entity.)

Here's the legal question: I suspect that he may have engaged in some sort of transfer of the vehicles between entities, even though both have retained their current NY registration. I noticed that VT, RI, and DC do not report to the national vehicle title database; would it be possible to title a vehicle in one of those states without NY finding out? Is this illegal, to then continue using the pre-existing NY registration?

I've been in touch with the attorneys handling the shareholder suit, but they currently have bigger fish to fry than some transferred automobiles (even though the net vehicle value approaches $100k). My more current concern is for the property owner, who is very concerned that he will become a major eviction problem in the not-too-distant future, and she is concerned that her property may be being used for some sort of illegal purpose that could put her at greater risk. The tenant is also a little unstable, and I'm a bit concerned that he could get in an accident - perhaps even deliberately - and could somehow disclaim responsibility. (I'm obviously not an attorney, so no idea if these concerns are at all valid.)

Any advice is appreciated; feel free to message me direct if this is too sensitive for posting. I know I / we should probably talk to an attorney, but it's very difficult to find someone versed in the various intersecting aspects here: business entities, property rental, and vehicle law - I am definitely open to a referral, though.

Thanks in advance.
-frank