Kiwior is a terrible option at LB and I am not sure what you saw in the Liverpool game that comforted you
I kind of agree with HCZ that it would be better to play Gabriel there, but the thing is I don't even rate Kiwior as a CB, or really I should say I don't rate him as a decent player at all anymore.
I saw somewhere that Tomi could be back, worth trying him out even if he can only play one half.