With regard to reading/teaching notation, I do not think it is a prerequisite. I no longer teach in any meaningful way, but the amount of students I taught to read was not huge at all. It was just not on their radar and not something they would need. They wanted to play songs they knew.
This could be done with TAB (not for me) or getting them to read chord charts for pitch and using their ears for rhythm. This enabled them to start playing their stuff and begin to play with their mates. In general I would let them choose what they wanted to play, occasionally guiding them. This made for motivated players. As they developed then some eventually looked at notation. Don't get me wrong, I believe that reading notation is a very good thing, but certainly, if you were teaching beginners then it is not an issue. Enthusing them is MUCH more important. And if they do power ahead and need notation, then pass them on (or use the time to get up to speed on notation).