What are the risks of reversing a data migration?

[cindy2023]

Due to quantity, my data was migrated in summary mode. I want to reverse the migration, clean up data, and resend in detailed mode. I was told, by support, there is a major risk in doing so.  What are these risks?

Insufficient data syncs with QBDT, if it even syncs at all. Several transactions, items, and bills keep repeating in the syncing process, either as created or update failed.

I have a number of closed tickets with Shopify support, all if which have not resolved my issues.

Looking forward to your suggestions.