I didn't get the purple highlighted story version Crisis on Umbara. I completed it on another character but it still should have appeared for the first time on this toon. Did I miss the prerequisite like Directive 7?

Iokath is the pre-requisite. The only thing you need to do Iokath is be level 70.

Iokath is the pre-requisite. The only thing you need to do Iokath is be level 70.

This, but if you still can't find it on the second character, do what I did on my second character to do it(1). Go to your class ship and look in the mission terminal near the big holoterminal.

 

(1) My first ever SWTOR character. My first character who did Iokath and Umbara was my second ever SWTOR character.