This man was Rofflash.

He had dragged Sally Salisbury some three or four yards away probably to prevent her interfering and persuading Vane not to fight.

Whatever their talk might have been about, just as Dorrimore turned Vane saw Sally tear herself from Captain Jeremy's grasp and hurry away, and he became more than ever persuaded that she had betrayed him.

What did it matter?
One woman or another--they were all the same.
He walked apart while Jarvis and Rofflash arranged the preliminaries.
His brain was numbed.

He did not care whether he lived or died.