Sorry, there is no direct way to have Monarch include data references in the page header or footer. This may be a feature worth considering for a future version of Monarch.
The key problem is how would Monarch handle data with more than one distinct value in the table.
Monarch lets you reference some useful data in the Monarch page header or footer, such as the report name you are using, model name, filter name or sort name (if any are in effect), etc.
That said, a "cheat" that might work would be to programatically change the report name to the report date, or create a copy of the report with the report date as the report name. Sorry I don't have something more concrete!
Product Marketing Manager