Hi,
When I unserialize the value, I see questions and answers are saved correctly:
https://www.unserialize.com/s/54991f6e-ab47-be68-7bdc-00006081513b
FYI, the group extension saves all sub-field values in a serialized array in the database (which is what you just saw). When you get the value, it will be unserialized and returns an array.