On Tuesday, the 17th July, you went, I believe, with another guest, to visit the dispensary at the Red Cross Hospital in Tadminster?
I know who it was that you went to the Red Cross Hospital dispensary with. 
mnli hypothesis: I know who it was that you went to the Red Cross Hospital dispensary with.  premise: On Tuesday, the 17th July, you went, I believe, with another guest, to visit the dispensary at the Red Cross Hospital in Tadminster?