My guess is that you might only have a “soft reference” to your data and that it is not taken into account by the cooker.
First, you can check in the cooking log if your file has been considered for the packaging or not.
Second, how do you use the data? Is it only via C++ with path? or is it a property that you set in a BP with your asset?
Last did you test with “LaunchOn” or Shipping process?
I’m using Datatable a lot on Android (didn’t test IOS yet) and it is working without any issue.