False positive. The UQ/CSL vaccine candidate used a very small piece of one protein from the outer shell of HIV to stabilise the SARS-CoV-2 spike protein in its "pre-fusion" conformation - that is, the shape it's in on the virus before it attaches to a cell. The shape you want to develop antibodies against if you want to block it from being able to infect. That worked fine - but unfortunately in some people it also caused antibodies to develop that recognised that tiny fragment of HIV protein. That's completely harmless to the people in question - there is no actual involved, remember - but causes some blood tests to register as HIV+ (because those tests generally don't look for HIV, but for the presence of antibodies against HIV).
TL/DR: this vaccine wasn't cancelled because of any risks to peoples' health. It was cancelled because it would have made it harder to screen the donor blood supply for HIV.
Oh, and nobody will be lining up for it because they won't be using it. They'll be using the Pfizer and/or Moderna vaccines, which have no such issues.
