Hi.
The loss record is as follows in the GenQu6Abt document:
http://www.ahs.no/ref_db/lw_loss_pub...?lossid=114282
This loss was on a 'Heimflug' as Christian mentioned, thus it is not possible that this flight was an operational flight with England as a target. Probably a training or transfer flight.
My best tip with regards to research this further is to try to get your hands on the Namentliche Verlustemeldung for this crew. As you have located the grave of Hennermann, you have both the birth date and date of death I suppose, and I would simply make a request to the WASt in Berlin for information on this loss. Ask specifically for any comment registered with regards to the loss reason as you no longer will be able to receive a copy of the NVM.
Regards,
Andreas B