The latter does line up with these renders in an official patent document for phone cases (the document doesn?t explicitly name the Mate 30, however). For a better look at this design, check out these non-official renders.
There?s not much consistency in the number of cameras either. Some rumors suggest 4 cameras, other say 5. Unfortunately, neither this leaked case nor the glass back from before can shed any light on this matter (if these are indeed legitimate leaks in the first place).
The Huawei Mate 30 is expected in September or October with a 5G version coming in December, so we can expect more substantial leaks in August.