However, in this situation, it appears to be a pattern rather than a one-time issue.

If they refuse or fail to do so, I suspect the insurer will tell its insured, the lien appears to be unenforceable and to notify them (the insurer) if a suit is filed to enforce it. 

It doesn't appear that there was anything wrong with the property.

Further context, I have zero debt, high 700s credit score, one other investment property here locally. 175k in cash available, looking to do DSCR loans or cash and then refinance.Peoria, Illinois- Great need for lower income housing, market appears to have many options.Lawton, Oklahoma- Looking only at extremely cheap properties, as it seems it’s not terribly hard to find renters.

I have used avail.co in the past with great success but it appears this software and others no longer market on zillow which I know to provide a lot of leads in the past. 

Alternatives are college courses, textbooks, and engagement through web searches.  

It appears you can publish and post but there isn't many other features.

And I love that you are cognizant of the appearance of impropriety. 

A low opt-out percentage appears like you have a clean list of people who initially opted-in to receive your messages. 

The rent prices I was basing off of rent estimates I found on the web, so I'm not sure if that is a factor, but I can reassess.