Hi Tas.quliter.
This trick may help you.
The last best shot at being able to read your serial number will take some tries, but it's worked for me.
Use the video feature of the iPhone to more clearly see your serial number that is faintly buried in that velvet material.
Set your iPhone to 4K, start recording video and activate the flash to blast the serial number area with light. Do a focus lock if you need too so that focus remains consistent.
Record video of the serial number location.
You may need to do several passes, where you can rub your fingers across the serial number location in various directions, in order to more clearly reveal the numbers.
If you area patient and do it just right, you will eventually be able to make out the numbers.
Since the resolution is very high, it will yield in my opinion a bette image than if done with a still photo. See image below:
Zooming in on the still is not useful. Don't waster your time.
Shooting video offers far superior results. So while playing the video back you can pause and pinch to zoom on the area, giving you a better chance to decipher that lost text.
Write it down, several times, several version of what you think you might see, even if you are not certain. You are bound to get that number right.
See the attached still pulled from a video file. :
This is from the last iPad Pro smart keyboard I had to replaces. I have replaced this keyboard three times. This latest version I can tell they made a minor design adjustment and so far, all good. The Serial Number issue has been resolved, features darker text, and the 3 pin contact ribbon no longer feels like its in the middle were the flexible magnetic strip is, where I think the problem started. After a year or less of flexing, that cable breaks.
I had the same issue in the end. They wouldn't replace the keyboards without a serial. I don't think it's fair to punish apple customers because of their bad design. Heck I didn't even know about this replacement program until I stumbled upon it on a forum thread.
By the way, do yourself a favor and get a screen cover for your iPad Pro, something made of Ballistics glass. I don't care what they tell you at that Apple Store, those screens can and will scratch over time. I returned two of these iPads early on because the Apple Pencil was doing just that. You won't loose anything in the visual quality.
All the best!
MJ from Bmore