The error that will prevent you to rehire an employee in the UI if "Ok to Rehire" field is set to No does not trigger when you rehire an employee through import.
The image below came from a demo instance, any similarity to a live customer data is purely coincidental.
SuccessFactors Employee Central Import
OktoRehire, No, Rehire, Import , KBA , LOD-SF-EC-EDP , Import Employee Data (EC Core only) , Problem
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