Hi Curtis, we have another option for you that can make this very seemless for your end users. They can add a parent record, upload an excel file during that add record process and when they save that record it would trigger our EZ File Importer add-on that would upload the rows in that excel file as child records to the parent record they created.
This is a non-native solution but its an option if you are looking for simplicity and consistency.
more here: https://www.juicedtech.com/ez-file-importer
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Keith Jusas
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