Bank Statement from South Africa?

I am a US citizen who will be working in China for one month and would like a friend from South Africa to join me on a tourist visa. I will provide tickets and hotel bookings for her. The Consulate in SA requires 3 months bank statement, which she does not have. Browsing answers for SA on this website, however, I see no mention of bank statements. I am wondering if such a statement is necessary, and if a statement from my Chinese work unit confirming my employment and from me offering to host her travels would work as invitation letter/proof of funds in lieu of a bank statement?

Thanks for your attention, Adam