Hi Amber,
I don't know if you are still working with this issue all this time later but we did have another feature come out that could be helpful in this instance, custom data rules. Custom data rules let you use the Quick Base formula language to put rules in place on when a record shouldn't be saved, you can even put in your own error messages when this happens and they work across any type of data entry including grid edit, import, and APIs not just form rules. So in your instance you could use it to write a custom data rule so that
If([Portfolio Approved by USACE]<[Portfolio Sent to USACE], "Approval dates for portfolios must be after date submitted to USACE")
I hope this is helpful and I have linked two help topics on custom data rules below.
https://help.quickbase.com/user-assistance/1/validation.htmlhttps://help.quickbase.com/user-assistance/formulas_custom_data_rules.html?Highlight=custom%20data
