T4.1 damaged, doesn't function properly

From my original email to Paul:
Around a month or two ago I took my Teensy 4.1 to school with me to show others. One boy grabbed it from me and proceeded to damage it on the ground with his foot. The board sustained lots of scratches, particularly on the topside. I don't know if any circuit parts were seriously damaged.

The T4.1 was still working after, until now when I tried using it again and it just stopped working properly. When I connect the board, it does not show in the Arduino IDE and shows as "SE Blank RT Family" in Device Manager. The board flashes the red LED three times when I push the (now mostly grinded off) Program button. I can't even do a 15 second restore; the red LED just flashes once at the beginning of the window.

Do I have a hardware problem with my Teensy 4.1? Any possible flash issues? If there are any serious problems, I already know where to send my board.
Could you guys help me out? I will get it sent to PJRC if you are out of ideas.

It could be fractured solder joints or broken tracks. A weakened joint or small fracture may work initially and then open up due to temperature / humidity changes.
Or it could just be good old ESD damage. If a board is getting taken to school and thrown on the ground I somehow doubt you've been following ESP precautions at all times.

Your post can be summarised as "A delicate piece of electronics was been abused in every way possible and eventually stopped working."
All PJRC will do is tell you that you've broken it. It's clearly not a manufacturing issue so they aren't going to do anything unless you pay for it. For this sort of thing unless the issue is both obvious and easily fixable it's cheaper to replace than to repair.

My advice would be to order a replacement and drop the current board in the nearest electronics recycling box.

About the only thing you could try is running a hot air gun over it to reflow the solder joints. It's a long shot but may work.