Hi Shaylynn, not sure on Montgomery specifically, but I just flagged this advice in another forum. 

This will give you insight into their financial health and stability.Look for any red flags, such as high debt levels or irregular financial practices.Understand Their Underwriting Process:Inquire about their underwriting criteria and process.

Testimonials are a huge red flag to me as they are difficult to verify and could be paid actors etc.

Requiring a wire is another red flag. #1 seems relatively normal

We didn't expect the fact that insurance should cover short term rentals but raises a red flag for lending during the 30-60 day period after closing where they make sure you're not using the home as a rental.

A wholesaler contacted me about this house they have under contract for $205,000 that they want to close on within a week for $220,000. The house is in my hometown, I'm very familiar with the area. The house is easily...

On the other hand if they are a sponsor that is experienced in stopping a skin in the game, that's a huge red flag for me.c) how open to scrutiny are they?

HUGE red flag. 

Negotiating a security deposit amount is not a red flag for me, especially with over $10K in estimated moving expenses (professional movers) and move-in costs (1st month and security).

Unfortunately, you ignored multiple red flags during the vetting process and now you're paying a price.