they dont get counted for their singles career title stat (obvio)…but theoretically talking if he plays a match in finals yes…if he plays till semis, and doesnt play in finals, then no…example : Nadal in 2008…usually its considered Nadal has 4 titles : 2004, 2009, 2011, 2019…but wiki does say Nadal has 5 davis cup titles but people usually dont consider the 2008…so it depends on whom you ask…