Well at first if you could, it would be enough to maintain a fork of the branch that interests you and use that to see it.
Regarding the database, you could use atlas if you wish, it is also a free option. However, it will not work quite well due to the limitations of the service, although if it is for development and testing it could work (although I recommend using it locally for that purpose)
According to the docs,
On typical installs of Redis, the main database is found at
and the file actually is there.
So, what is the dump.rdb in the nodebb root dir?