Is this Beefsteak fungus in an oak tree?

Is this Beefsteak fungus in an oak tree?

Observation - Is this Beefsteak fungus in an oak tree? - UK and Ireland. Description: Spongey rather than rounded spores, leathery brown cap and located deep inside the split trunk of an oak tree (see third photo) and below waist level. I'm thinking Beefsteak fungus but I'm not sure about the darkness of the cap...

Spongey rather than rounded spores, leathery brown cap and located deep inside the split trunk of an oak tree (see third photo) and below waist level. I'm thinking Beefsteak fungus but I'm not sure about the darkness of the cap...