Hi @atracksler,
Adding to what expert suggested, please try testing the behavior in Safe Mode to rule out any third-party interference during the packaging process (Ref: https://adobe.ly/4r1ueU4). You can also check this similar community thread where other users encountered the same issue: https://adobe.ly/4p9Xp5s.
As noted there, the problem seems tied to how InDesign interacts with NAS volumes connected over SMB on macOS 26 (Tahoe). The team suggested trying an AFP connection instead of SMB, as this often resolves the issue. Please give this a shot and let me know if it helps.
Looking forward to your update.
Abhishek