Thanks Martin,
My friend has found a 115 Sqn Roll of Honour - compiled from 115 Sqn Records which does indeed state the reg was "H2" So, the truth will likely never be known. For anyone interested it appears the aircraft was shotdown by Walter Borchers, a very successful RK 59 kill ace, himself killed in 1945.
There's a nice picture of RP Maude and his crew, along with one of their immaculately maintained communal grave in France here:
http://aircrewremembered.com/maude-ronald.html