Foster led the attack for South Africa after coming off the bench against Namibia on Thursday but his afternoon only lasted a minute after sustaining an injury to the back.
Dolly gifted the hosts the lead in the second half but Zambia hit back two goals in the final 15 minutes to secure victory.
"If you lose a player in the second minute of the game, it messes up everything. I think it was a huge setback to lose Lyle in the beginning of the game and the plan was not to make substitutions as early as we did," the Bafana mentor told SABC.
"That did not give us the rhythm that we were looking for. We kept on giving the ball away. In the first half, we played like a team with no confidence and that's what really killed the momentum in the team. We gave away too many corner kicks early in the game.
"I tried to push them, to give them the confidence and the belief. We spoke about it at half-time, we addressed the issues we saw in the first half. And that's why when we started in the second half, it was a better performance.
"When you concede two goals in a game like this in the second half, there are a lot of questions you need to ask yourself defensively. These are professionals. They are fully aware of those situations. We'll go back and look at the game itself and do the analysis and when we report for camp, we will be addressing those negative issues.
"I think it was good preparation. This is the game that for Micho was very important. He is at the bottom log. We are also trying to get to the top of the log. The question was; are the players going to be ready for the AFCON qualifiers next month? And I think they have answered those questions."