Two weeks ago, a small group of UK activists protested at the LSE, calling for Mahlangu to attend the arbitration hearings. It was then revealed she was not studying there. Mahlangu's attorney said she had never been studying at the LSE.
The evidence leader at the arbitration hearings, Patrick Ngutshana, testified last Monday that Mahlangu had agreed to appear at the hearings between January 28 and 31 2018.
Judge Dikgang Moseneke, however, suggested she be subpoenaed.
Moseneke said he would not consider the hearings closed until Mahlangu and two other senior officials had testified. "Steps must be taken so we have them here. We are not going to run out of time," he told advocates.
A local subpoena does not have legal jurisdiction outside of South Africa, explained criminal attorney Ian Levitt.
The hearings resume on Wednesday.