I don’t think so. To my mine the only way would be if you had done a backup, edited the file that was on the device then restored your ipad from that backup to put the old file back on....which would be very tedious and time consuming and also result in the loss of any other data that was on your device and not backed up.
You can send apple feedback and let them know you’d like the feature
Product Feedback - Apple
Or develop a work flow where you copy the file elsewhere before you trim it. I was able to copy a very short memo into my notes app and there may be other ways to move it to the files folder or elsewhere to preserve a copy before editing so you could revert back to that (Although I‘m not sure how to get it back into the voice memos app)