Dear Karl, Norbert and Nick,
First thanks for your comments and support, I also thought of 'vor Bach bei Greven' because it would make sense that a plane produced in Rostock during its delivery to Münster-Handorf could have made an emergency landing before reaching its destiny. The only doubt is the very detailed description of this landing 'near a creek' without specifying which creek. So that info is quite unrelevant it seems.
On the other hand: the combination of 'Vorbach' and 'Beugreven/Beigreven' makes no sense either...
At the moment I accept Norberts explanation as most likely version, having no credible alternatives.
Nick, the identities of both He219 named in Ultra are these:
'097' refers either to 190097 (there are other examples of He219's with only the last three digits on the tail section)
or He219A-097 which would mean that Wnr. 190225 was meant. I do hope the last option is correct, that would imply another identified fate of a He219 because so far I have no single reference/report for 190225.
The He219 (Wnr. 420328, a He219A-2 produced in Schwechat) was flown by Hptm. Alex Graf Ressequier and was damaged by a RAF Mossie.
All the best, Marcel