I do not know if they have just changed the procedures, but i got my mother-in-law's tourist visa from Airport immigration like one month ago.

If Airport Imm. gave you a clear answer, you should apply to Gharraffa then.

At Airport or Gharaffa, do not forget, you will need a document to proove the relationship (family registration documents from your origin country, attested).

Or you can go ahead with Hotel tourist visas, which will be rather costly.

All the best