Maritzburg chairman Farook Kadodia confirmed the switch has been agreed in principle, but says Ndlovu must still finalise personal terms with the Absa Premiership champions.
"The clubs have agreed in principle on the terms. The player still needs to agree terms, he hasn't signed yet," Kadodia tells KickOff.com.
According to sources, the clubs negotiated the move when the Brazilians signed Lebahang Maboe from the Team of Choice in August.
"Ndlovu was long [ago] signed by Sundowns and the deal was completed at the same time as Maboe," says a source.
The source, who says Ndlovu's efforts have been questioned since the developments unfolded, initially had his heart set on joining Orlando Pirates, but Maritzburg received a better offer from Downs.
"Actually Ndlovu wanted to go to Orlando Pirates, the club he grew up supporting but their offer was little compared to Sundowns', and the chairman said he'll take Sundowns' offer, not Pirates'."
Ndlovu was named the PSL's Young Player of the Season and Midfielder of the Season in 2017/18.
However, the 22-year-old has made a slow start to the new campaign, featuring four times as he had to serve a two-game ban for a dismissal against Kaizer Chiefs.
Bafana Bafana coach Stuart Baxter decided against calling up Ndlovu for back-to-back African Nations Cup qualifiers with Seychelles this month.