‘Mshishi’ underwent surgery back in October, after suffering an Achilles injury while on Bafana Bafana duty, and has yet to feature since Cardoso took over from Rulani Mokwena two months later.
The 35-year-old was spotted in full training this week, sparking suggestions that he could soon be back in action, but Cardoso says they are being cautious when it comes to throwing him into high intensity situations.
"Themba is growing his condition, I told you that we had a plan to bring back the players that were injured – because now Themba is not injured – normally and bring his condition up so he can play," Cardoso confirmed.
"If it will be tomorrow, or the next day, or the following one, I don't exactly know. But is he available? Yes. Does he for sure still have some restraints from the capacity to play a 90-minute match on a level like Champions League? For sure, he has."
In addition to the Champions League, the Tshwane giants also have seven crucial Betway Premiership fixtures to defend their title, with Cardoso hoping Zwane and centre-back Mothobi Mvala, who is also returning to fitness, can help carry them over the line.
"Let's see how he can help us, and let's see how we introduce him in the dynamic of the team in the best possible way, that's what we've been doing in the last few weeks," he added.
"We are a bit happy, not only with him but Mothobi – who's not exactly at the same level but he's coming back, and I believe until the end of the season, they will still be very important for us – that's our [main] concerns, of course."