Hi HB
First the good news, there is absolutely nothing wrong with your Lumix G6 video, in my two NLE's the clips open and play correctly, the resolution and clarity is fantastic.
I had major issues with MP4 video when I had PD9 installed which led me to eventually removing it from my computer and seeking alternative programs. The two programs that I now run in conjunction with each other do not have any issues with MP4 videos.
PD has always been my preferred editor and maybe one day I will install the latest version, however you cannot upgrade from PD9 to PD12, it being necessary to purchase the full version, which is a bit of an imposition, seeing as other NLE's allow you to upgrade from just about any previous version installed
So, you could try downloading the trial of PD12, although there might be some limitations on the file format that can be trialed with it, MP4's used to be one format that could not be used with the trial, that may have changed now.
Robert
Intel i7 930, 16GB ram, Radeon HD 5770 1Gb,Ver. 14.12 Win7 64 bit
Intel i7 7700 HQ, 16 GB ram Nvidia GTX 1050Ti 4GB dual drives 1 TB SSD + 1 TB HDD Win 10
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