One quick test recommended for me is to convert the columnar tables to heap. Upon doing it, the query worked. It was hung in the first attempt but in the second attempt worked fine.
I would to get this resolved for columnar setup.
There's no such thing as columnar in PostgreSQL. You must be using either a fork or some pretty complex extension. It seems pretty clear that the problem is in that code and not in PostgreSQL since it goes away when you switch off it. So you're probablh better off reporting it to them.
