I have had a WCAG AA 2.0 audit failure doing this because this approach is not obvious to a sighted keyboard only use that space bar and arrow keys and not tab

I have had a WCAG AA 2.0 audit failure doing this because this approach is not obvious to a sighted keyboard only use that space bar and arrow keys and not tab + enter is the control mechanism. Also a non sighted user will need hidden text before the tabs at a minimum to explain how they work.