Subscription groups and recruiting use case question

Hi Theresa! This is an interesting use case. I'm happy to share some thoughts here. 

First, I think these are 2 separate use cases: 
1. Set up the email preference center and subscription groups. 

2. Set up an IAM that subscribes users to the newsletter subscription groups. 

For #2, you may be successful with the trigger "interact with campaign" --> Clicks IAM button 1. And then you'll have to set up a webhook to add the user into the Subscription Group. 

I'm curious also, so I may do some testing on this one from my end! Let me know if you have any questions in the meantime.