New LR Classic User

Good afternoon. I am a new transplant to LR Classic following years of using LR6 on a 2013 iMac running Catalina. I purchased a 2018 Mac Mini and monitor to take advantage of the latest IOS as well as the newest iteration of LR Classic. So, muggins here attempted to transfer my 13K photos off of LR6 to the MM via a external drive. I followed the suggestions for transferring. Suffice to say, when I thought all was good,

I deleted the files off of the external drive and trashed what was in the trash.. Come to find out not all photos tranferred and I lost between 4K-5K photos.. So,, my thought is to delete the entire collection of photos off of LRC and start again by sorting the remaining photos on my old Mac and then transferring the remainders over to MM via the external drive. Is there any hope to find the lost photos which were deleted and deleted again before I go back to square one. Thanks.