Hi,
Please provide more details about how the data was imported to Excel, so that I can understand the whole scenario better.
Based on my knowledge:
1. If the data was imported to Excel, the text file itself isn't changed, there is no need to re-sync it to OneDrive.
2. One possible cause that I can imagine, is that the text files are still occupied by Excel(depends on how you imported the data to Excel), so OneDrive doesn't sync it to cloud.
Please feel free to post back and provide more information. If I misunderstood anything, please feel free to let me know.
Regards,
Melon Chen
TechNet Community Su