Hi TWZ, thank you for joining our forum!
There is no need to download (displaylink) drivers for the MST Hub since there is no Displaylink (video) chip inside. The MST Hub works as a splitter as long as the DisplayPort 1.2 port on the source device supports Multi Stream Transport. No installation of drivers is needed.
Which Macbook Pro version are you using and do you know what Graphics solution is inside?
Macs are often picky eaters when it comes to supporting non Apple technologies. In this situation it may be possible that Multi Stream Transport is not supported and thus the monitors show a mirrored image, which is supported under Single Stream Transport.