It works!!!!!!!!
I unlocked my broken HTC A9 that was encrypted with a PATTERN LOCK. YES!

I used an Insignia OTG cable, and a logitec K830 TV USB keyboard that had a mouse touch pad included. I did have a replacement phone that helped me make sure the touch pad was working, and practice the pattern. My screen was almost completely black so I had to literally use a ruler to measure the exact location of the dots on my screen. I used lipstick (so I could remove them when done) to mark some dots on the cracked screen to help guide me. After approximately 3 trials (I had about 6 left before my data was erased), I was able to unlock it, connected it to my laptop, and recovered every single one of my photos.
THANK YOU SO MUCH! Don't give up!