I just did a test of something. I tested with SketchUp, but I think it would apply to LayOut as well.
I manually put a copy of a file into the recovered files folder that SketchUp uses, then opened up the real file from the File, Open Recent… menu. That showed a dialog asking if I wanted to open the auto recovery file that existed. I chose No. That gave me my normal file. I made changes, saved, and tried again. Still I was offered the recovered file, even though it was now older than the real file.
Then I opened the Welcome screen, and it also showed the recovered version. I chose that, and then instead of a simple dialog box I was shown two thumbnails, one for the recovered version and one for my real file. I chose to open the real file, and a warning appeared to say that the recovered file will be deleted. Indeed it was.
I did that same last test in LayOut, and chose one of the welcome screen recent files that showed Recovered across it. Again I opted to open the normal file and not the recovered file, and was warned that the recovered file will be deleted. After that, the recovered version didn’t appear in the recent files.
So, long ago you had a crash, that left the auto save file still sticking around. If since then you have opened the file from Open Recent, and possible from double clicking it in the Finder, the recovered file hasn’t been given a chance to be deleted.
Close the file, open the Welcome screen, choose the recovered version, and then when asked, open the regular one, and confirm deleting of the recovered version.