Hypholoma toadstools on Granta Park

Andy M saw these toadstools on a rotting oak tree stump near the river on Granta Park,  The caps were around 3-5 cm across, and he believes them to be one of the Hypholoma genus, possibly the so-called 'Brick-Tuft' toadstool (H. sublateritium), or maybe the 'Sulphur Tuft' (H. fasciculare).