A long shot but you can try this e-mail
spurensuchesh@gmx.de.
This guy is studying crashes in Schelswig-Holstein (sp?), so more north, but may have info on battles around Hamburg, or contacts with German researchers in the right area.
According to the 156 Sqn report (
http://www.156squadron.com/display_m...?MissionId=247) the squadron was engaged by Me 262.
According to an entry with no given source in the
www.crashplace.de database (search by date, 31 März 1945), this Lancaster was probably shot down by Oblt Fritz Stehle of 2./JG 7 and fell bei Rotenburg an der Wümme.
Good luck
Laurent