Joanna Cherry has a protected belief, a protected characteristic.
The staff refusing to work because they feel 'uncomfortable' about a lesbian because she believes that biological sex is important is no different to refusing to work because they feel 'uncomfortable' about platforming a black person, or a trans person, or a disabled person etc.
Your staff being intolerant bigots doesn't make discriminating against someone because of their protected characteristic legal.
But you've spent enough time on this board, and post pretty much the same on every similar thread, so you already know this.