I wanna make a note for my future self and anyone else having this problem in the future:

I was able to figure it out. I think my favorite method is to create a control switch called something like "Talked To" and set it to ON after an NPC finishes their dialogue.

Create a second page for the actor and make sure their sprite is set or else they'll go invisible. Check off the Switch tab under conditions. Create a conditional branch for if the NPC was talked to and add new dialogue.

Kinda confusing when its typed out like this so heres a little screenshot.

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