HeyGen and Storyline Integration Tips?

I'm trying to make a video with HeyGen using one of their avatars. I want him to introduce the course and then later another avatar incorporated as a Mentor for when the learner is having issues.

I want to make the avatar video piece more visually appealing. Like have words come up on the screen to highlight important things. I'm having a HECK of a time getting these to work in HeyGen. Like pull my hair out hard. I've wasted WAY to long trying to do this. 

I'm wondering if it would be easier to just get the avatar the way I want and then bring him into Storyline and add triggers to make the text appear within SL. 

Has anyone done this before? Any tips? I'm new to HeyGen but very familiar with video making tools, Vyond, etc. It can't be this hard, can it? We have a paid HeyGen account, but it is really slowing down my process. 😒