If the story is true ... then it would confirm that the attack on Melania was merely to provide cover to frame the NE story as a retaliation.
I would doubt that.
If the story is true...there's nothing Cruz could possibly do besides stall for a few days. A week at most.
Accusing Trump of feeding the sleaze to Enquirer would not affect the macro impact of the story in the slightest.
In fact, IF Trump were involved in some way I doubt that would even warrant a footnote in the history books...if the story is found true.