Why does my retina display not turn on after battery replacement?

The battery in my old Ipad Mini 2 Wifi w/retina display only lasted about 1-2 hours and it sometimes got stuck in mode where battery indicator appeared but didn’t charge. I decided to get the ifixit battery replacement kit. I followed the 55 step instructions to remove the battery and did the reverse to install new battery (note that I did turn it off first and I did disconnect the battery first). Now everything seems to work except for the retina display (the backlight seems to work but not the lcd display - nothing shows up when shining a bright light on it). I have tried the following with no luck and am looking for any other suggestions:

• Charged new battery for over 8 hours
• Re-started multiple times by holding power button and home button
• Tried disconnecting the battery, touch screen and lcd connectors and re-connecting
• Connected to iTunes on my PC (note that I had to guess where the number keypad was on my screen in order to unlock the Ipad. I did back up the Ipad on my PC just before starting the repair). ITunes says the battery is at 97% or so.
• Used iTunes to reload the software (I have not yet tried to “restore”)
• Locate Ipad using apple “find my” app from my phone and get Ipad to make sound
• Tried Siri - she responded when I said “hey siri” but does not respond to questions after that.

I’m wondering whether I damaged a wire or connector or the LCD beyond repair (I didn’t see any damage but these parts are rather small). Any hope of getting LCD to work? Thank you!