BuddyPress.org

Hi all,
First of all, this is my first time posting here (or in any other forum like this actually) so apologize if I’m missing info or something is not clear. Also, I have very little experience extending WordPress plugins.
I’m working on a community + e-learning site using BuddyBoss and LearnDash, and there’s an apparently little thing that I need to extend from the base functionality that I don’t know how to develop.
What we need to achieve is to somehow have paid groups. We have MemberPress, which allows us to do so, but the problem is how to take the user to the correspondent membership page when they try to access a paid group.
The solution that comes to my mind is to somehow change the default behaviour of the Request Access button on Private groups so that, based on a variable of the given group (that could contain the URL of the associated membership), it redirects users to the membership page.
I find myself with 2 problems here:
1. How to add a “field” to each BuddyBoss group that I can use to fill it with the MemberPress membership URL or ID that gives access to that paid group.
2. How I change the behaviour of the Request Access button so it reads that field and redirects the user there instead of doing what it currently does. Ideally, if the field is blank, the Request Access button should behave as default.
Do you think this is overall a good approach to the problem we have? Any ideas on how to solve problems 1 and 2?
Any help is much much appreaciated.
Kind regards,
Ignasi.