Formula Query for null dates

I'm trying to create a rich text button which will open a report where certain dates are null.  I've verified by running the report manually that the report does find results however when I use the rich text button I get no results.  I've tested in both the button and in the developer.quickbase.com site and have confirmed no results in both places - thus I'm positive it's something to do with my query structure.

The query I've passed is:
"{94.EX.8}and({24.XEX.''}or{25.XEX.''}or{70.XEX.''}or{71.XEX.''})"

Fields 24, 25, 70 and 71 are all Date fields and 94 is the related record.  What I'm trying to achieve is "Show me all results where any of the 4 date fields are not null".

TIA!