Cannot open CR2 in Photoshop CC 2022

On our Mac computers, the last two image cards we have downloaded will not open CR2s in Photoshop CC 2022. Both are running macOS Monterey V12.4. We have a Synology DiskStation server. The CR2s will open on the PC just fine, as well as those stored on an external hard drive. The Macs give us an error message of can not open because of disk error. or Could not open “IMG_0140.CR2” because the file is locked, you do not have necessary access permissions, or another program is using the file. Use the ‘Get Info’ command in the Finder to ensure the file is unlocked and you have permission to access the file. If the problem persists, save the document to a different file or duplicate it in the Finder.

The files are unlocked and we have permission to access them. I copied them to the desktop and they open, so I believe it's a server issue. Here's the thing: we can open all CR2s previous to these two shoots and they are also on the server...help! We can't store and work off the internal HD, we need the server for the sheer volume of images we deal with.