may be you haven't found it, because you searched too late in the year? Here I found it usually in the late winter days and April usually is at the very end of the fructification period. Usually you see at this time only the holes in the cortex of the hazel nut stems .... When you look in older Corylus bushes with stems covered by Hypoxylon fuscum, there is a good chance to find Encoelia furfuracea too. To my experience mild winter periods to February are the best time.