extract/work with partitions inside full eMMC chip dump (EFI-Qualcomm) - Android Q&A, Help & Troubleshooting

I have a dd-like dump from the emmc flash chip of a dead LG G3.
This is how it looked in Windows device manager when the chip was connected to the MMC reader:
{
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"lightbox_error": "The requested content cannot be loaded. Please try again later.",
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"lightbox_stop_slideshow": "Stop slideshow",
"lightbox_full_screen": "Full screen",
"lightbox_thumbnails": "Thumbnails",
"lightbox_download": "Download",
"lightbox_share": "Share",
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}
How can I get the individual partitions out of that file so that I can further work with that data? Eventually down to the file level. Mounting the individual partitions should be no problem (?) once I get to them.
But so far I am running into lots of problems and all tools and methods described seem to be for somewhat older devices that does not work with EFI structures. Mounting the whole file under Linux with losetup and as loop only throws errors or empty stuff.
My dump file starts with
Code:
EFI PART....\...~Bƒ4............
And that's where I believe the problem lies. The farthest so far I did get with testdisk - it recognizes some partitions and can even get to the files. But it does not, for example, recognize the partitions' names (aboot, boot...) even though the names are right in the beginning of the dump file.
Isn't there an image manager or something to deal with this stuff, prefer Windows and GUI for that?