Action Centre MUST rule on table columns

Hi,

We have a document understanding use case where some fields in some tables must conform to a distinct set of codes or names, such as here:
image

Now, these tables are not always present on the document, so it is possible they should correctly be completely blank. We would like to have a MUST rule in place on the table column in the picture, but the problem is if the table is correctly blank, the MUST rule prevents the action from being submitted as a blank table counts as the condition not being met. Hence we have put a SHOULD rule in place, but we are finding the users like to just ignore this!

Is there some way to apply the rule so that it only matters if the table is actually populated?