I have never bought multiple liens at one time (from another lien holder).

The current note holder may Not be the last mortgage holder you find in the public doc.s.

That's a perfectly reasonable approach to doing real estate investing.However, that post said nothing about buying or selling notes, or locating note holders or buyers.

The LLC has the first deed of trust on the property and it also is the Holder on my promissory note.

You Are buying the Property, thru a foreclosure action initiated by the second mortgage holder.  

I saw a renter hanging a jacket on a swinging planter holder near the gas stove and thought, they could burn my place down.

I’ve noticed that there are much fewer 3bed voucher holders than 2beds and 1beds.

A simple double check is that the Due on Sale is on the table; if the Mortgagtor and the TItle holder matched it wouldn't be a problem. 

If not, how would you proceed with tracking down the title holder?

They will be quickly acquired by larger and more sophisticated investors and not offered to the public.The decentralization of ownership through tokenization may paradoxically lead to a concentration of ownership, control, and profits in the hands of large institutional investors, and will lower return rates for shareholders.My PredictionWithin 100 years, most commercial U.S. real estate will be controlled by BlackRock and Vanguard, with major token-holders being retirement account and pension owners.