I think that I am experiencing this also .... I anticipated claiming one tripe that I knew I had shot down......the ROF screen said that I got (to my surprise) three, so I claimed three tripes...... PWCG 16.0 gave me four kills, adding a Sopwith Strutter that I know that I definitely did not shoot down..
I think I'm seeing this as well, but I'm brand new to both Rise of Flight this weekend and to PWCG, so take that for what it's worth.
I started one career, flew one mission and know for sure I didn't hit ANYTHING. I also didn't claim anything when submitting a report, yet in my career it awarded me with a kill.
I thought perhaps I did something wrong, so I started a second career, flew one mission, and the same thing happened. I didn't claim a kill in the "Submit Report" menu (was at 0) and in game I had zero kills as well. Yet PWCG awarded me with a kill.