Can you see the presentation file inside your thumb drive? If not, then TMP file may help you restore them or you need a third-party recovery software here. I don’t know much about such data recovery software since I never used any. But if the PPT file is there inside your thumb drive, then there are fair chances to repair it by using Open and Repair.
If this doesn’t repair your PPT file, then you must go for a third-party PPT recovery software. I have used such a software in my past. It was PowerPoint Repair Kit software what I used to repair my corrupted PPT file. You may check its free demo version as I did.
I came to know about this software from this article.
Hope this information will be helpful.