Another way is get Live Professor Free it is a VST/i host you can slave to Realband's Midi Clock output ( Options > Prefs > Midi Out just check all the boxes to start with)
You can use LoopBe1 - Download your free copy Virtual Midi Cable. In RB Midi Drivers Output set it as the second highlight one down so it's not the default and in Live Professor Free in Midi Setting set it as Midi Clock.

I used Banana VB Cable and set Live Professor Audio to "Voicemeeter AUX ASIO" and RB to "Voicemeeter Virtual ASIO" and set the Hardware out to your sound card.

Also > View > Tempo Panel have the Sync on.
See below the big RB clock and the little Live Professor clock are synced (RB set without 2 bar offset just to show).

EDIT:
In Biab you can set > Midi Option > Output Sync/Start info: Syncs Band-in-a-Box with an external sequencer.

Live Professor RB.mp4