File visible on Android device while copying via MTP, then disappears as soon as transfer completes...why?

Linux Mint 19.3 laptop copying a 400 MB file via MTP (in Caja) to an Android 7.0 tablet. While it's copying, the file is visible in the stock Files app on the tablet, and I can keep hitting the refresh button on the tablet to see the file size grow in sync with the progress meter on the laptop. As soon as it reaches 100%, it's still visible on the laptop, but disappears from the tablet upon the next refresh, never to be seen again. Even after unmounting and remounting, the tablet cannot see it, and the laptop still can. The laptop shows the proper file name, size, type, and location; however, it: - Shows "unknown" for "size _on disk_" and "accessed" in the Properties dialog - Shows a modified date of 31 Dec 1969 - Gives an generic i/o error trying to open the file - Gives the error "Sorry, could not rename ...: libmtp error: could not set object string" if I try to rename it I had heard that MTP support in Linux was pretty good nowadays. Before I try installing extra MTP packages and whatnot, am I missing something obvious?