iPad Pro trade-in value revised to $0.00

Hi, I bought a new iPad Pro and traded in my old iPad Pro. The trade-in value was initially $115.

My old iPad Pro had nothing wrong with it, I thought, except for battery life. (Apple wouldn't change the battery & there are no brick & mortar places near me that would change the battery for a reasonable price in a reasonable amount of time.)

Frankly, I was not even sure that I wanted to trade it in. But I mailed it back in its original packaging (I still had it) because the trade-in box that Apple sent was actually the wrong size (too small).

My trade-in value got revised to $0.00. I rejected that and they are supposed to send me back my old iPad Pro.

Reason for revision: "LCD display burn in damage/streaks/discoloration across the screen." (I have serious doubts about this. I never noticed streaks or discoloration on that screen.)

My question: Did somebody have to open up my old iPad in order to make this determination? I am concerned that I will receive my old iPad in worse condition due to what happened during this evaluation.

Before I mailed it in, I did not take any photos or videos of my old iPad & the packaging that I used. So, I have no proof of the condition of my old iPad.

Moral of the story: if they're only going to give you $115 and you are on the fence, forget it. Don't mail it in.

Really disappointed in this entire situation.

Thank you in advance.