Wasn't aware of too much of a headwind. The bumps, heat, dust etc add up to a fairly tough set of conditions, so the wind is just another factor to add in - could be head, could be tail...who knows? The trip I was doing was a major event sponsored by UNESCO, which helped us get into places like the mines. I don't know if they just take people in any old way. We did phone ahead, but we had plenty of contacts because of the nature of the tour. Worth a try, though. No bits of gold hanging around on the floor, unfortunately.
I was using a Monoporter trailer for this section of the trip, so could carry more water. With bags, bottles etc we could each carry 17 litres max at a time. Drivers will usually stop and top you up, but it's a fairly busy route rather than an out of the way 4x4 track (despite how it looks on the map) so not everyone moving along it will be exploring (and so won't necessarily have the same frame of mind as you). The trailer worked very well - max load on rough roads is 15kg (I think), so not huge but it handled great.