The winger, who lost his life in a vehicle accident on Monday morning, was supposed to move from Free State Stars to Wits at the end of the season after signing a pre-contract in January.
Jantjie is the second player from Ea Lla Koto to die in a car accident after Richard Henyekane passed away in 2015.
Mulovhedzi, of Rush Hour Sports Management, says he learned of his client's passing through Stars general manager Rantsi Mokoena.
"What I can say is, this is sad news, it's sad the way this boy left us. Rantsi called me early in the morning at 6am to inform me," Mulovhedzi tells KickOff.com.
"What hurts is I had managed to get him a contract at Wits that was supposed to start in two months, his contract was worth R4.5-million at Wits.
"I spoke to him yesterday [last Sunday] and he was telling me that he wanted to leave Free State Stars knowing that the team is safe [from relegation]. He said he wanted to score against Baroka and Highlands Park.
"We had already found a house for him in Joburg, and another thing again we made an investment at Old Mutual. Another thing is I was his 'parent' because me and him we talked about everything. I scouted him in Cape Town, now I'm doing all the arrangements [for his funeral].
"The boy was going to get a lot of money now at Wits to secure his future. We didn't get any money as yet from Wits, they were supposed to give us money at the end of the season. He was going to start to get a salary from Wits in July.
"Now what is going to happen is I'm going to meet with Wits before I say anything about Wits to avoid what happened to the likes of [Emiliano] Sala [the Cardiff City player who recently died in an aeroplane crash], so I'm going to meet Wits to sort out that issue."
Despite his talent and fame, Jantjie would always have time for the media.
"He used to take my advice, he was a good boy who loved people," Mulovhedzi adds. "I used to tell him how journalists made him who he is today. I used to explain to him how important you journalists are.
"He had signed a four-year deal with Wits, they are the ones who will tell us what is the way forward from now. I'm the one who is doing everything now because he had no parents, I was a parent to this boy, he had no parents. He's got two children. My worry now are those children, whatever he has left behind now is for his children."
Meanwhile, Stars' league fixture against Highlands Park this weekend has been postponed to a new date yet to be confirmed.
CONFIRMATION OF OF A FIXTURE POSTPONEMENT:— Official PSL (@OfficialPSL) April 2, 2019
The #AbsaPrem fixture between @HighlandsP_FC and @FreeStateStars which was scheduled to take place on Saturday (06 April 2019) has been postponed to a date to be advised.