NJ
If you were in cowboy country it may be too long after the event - do you have a timing for the RVR that you were given? I am not going to get involved in the rights or wrongs of the situation as there is insufficient information available other than to speculate that if you can see the runway from the point at which you have to make the decision do you not, by definition, have the appropriate visual reference? Those of us that have had to operate in some of the more forgotten or ignored corners of the world probably appreciate your dilemma.
Operating into Khartoum many years back and the "actual" gave the weather as well below limits but the "actual" was four hours old, if I remember correctly. Fortunately we managed, after a delay of about 20 minutes, to get something a bit more relevant and, as anticipated, it was fine. Being where I was at that time of day and at that time of year I was planning to continue anyway to have a look for myself.
Good luck.