HB, capital [ house ] over pension age

My client separated from his partner and now lives in lA supported accommodation, the partner live sin the former home, jointly owned with the partner who is unwilling to move or allow a sale, HB has now stopped after 26 weeks as my cl is deemed to have capital over £16.000,
cn my cl challenge this as he cannot access teh capital value of teh former home in which his estranged partner is living, no children living in the house
so its down to the valuation of teh former home, is it nil or not ????????

I assume he does not qualify for Pension Credit?