Hi Vadim,
I agree with you. There should be a commit work at the end of the inbound proxy call which the SAP takes care some where else when passing data to PI. Like in case of outbound where a commit work is mandatory after calling the method without which the data is not passed on to PI from ECC. In the inbound case we are not writing the commit work side by side as against the outbound case. I saw your logs that's detailed enough. Now this becomes the normal activity for the inbound without a doubt.