I think the bed task is last because it talks about the sprint to the pitstop for several teams. And Marcus says "Most important part of the leg for us, and our cab breaks down" when the bed is in the trunk of a car. "most important part of the leg" = close to the end?
I believe Marcus and Amani just got bad luck when their taxi broke down and that's how they are at the back of the pack - maybe right before the tobaco task?
My guess is that it's safari trip to the School,
Detour at the school one where cartons are made (toys for the children - Sandy tells Jeremy to enjoy some of this, because the kids are all excited??) and/or whatever Cathi seems to be doing (clothing),
then Roadblock Tobacco task,
then bed task,
sprint to the finish (while carrying the beds?).