Foster had an excellent chance to give Amajita the lead just before the half-hour mark, showing his immense strength to burst through the Zimbabwe defenders, but his shot clipped the post.
It was Zimbabwe who broke the deadlock against the run of play, a poor back-pass from Ngcobo giving Murimba the opportunity to chip Kubheka and score his fifth goal of the competition.
Kubheka, who is loan at National First Division side Cape Umoya United from Mamelodi Sundowns, did not need to rush off his line to the edge of the box when there was defensive cover.
It was the first goal SA had conceded in Zambia.
Amajita were level on 84 minutes, though, and it was Foster to the rescue again.