How can I get users to follow a Chatter group from within a record?

I want to add a group chatter feed to a record.

I used the solution detailed in this community post which got the group feed in the record.
Users can view the feed, post on the feed, download content from the feed but are unable to follow the group from here.

When they do so, they get the following error message.

I used the following code in the template:

<iframe frameborder="0" width="100%" height="800px" src="/apex/skuid__Social?id=0F937000000HByQ"></iframe>

0F937000000HByQ is the id of the Group.

How can I get users to follow a Chatter group from within a record?

You’ll need to add a record to the EntitySubscription object with the ParentId & SubscriberId provided.

Just tried this, but it seems like EntitySubscription does not encompass Groups.
I tried adding GroupSubscription got this error on the skuid page instead.

any idea how to turn on that feature it’s asking for?

I think you are running into a setting in core salesforce, rather than in Skuid.  I suspect you’ll have the same error message (from the first window) if you try this with the standard Chatter layout. 

Rob, is it possible to hide the Follow button on the group Chatter page?