How is it that the raw DNG file size of the Pocket 3
  is around 17mp when the sencor is only 9.4 mp.

Hi there. Thank you for reaching out. We will coordinate this with our relevant team for further clarification. I will keep you posted.

Hi there. Thank you for reaching out. For DNG files, please check the actual size in PS software. If you still experience the same issue, please provide us with the original image file for further checking. We appreciate your understanding.

There is no issue, the file size has no direct relation to your mega -pixel count, the file size will vary depending of the scene complexity, and a raw file is mostly uncompressed