Using parking guard is something new to me though i have been in this game for a long time, but it is not on a viofo camera i do that. ( i do have the new A139 for testing )
The way i understand it the appropriate viofo HK3 hard wire kit is a 3 wire kit, so if that is the one you have, and the camera record fine while the car is on, then you might have the two +12 V wires mixed up, so the ACC one are on a always live circuit and the BATT one are on a ACC circuit.
As i recall the yellow wire is the one that go to a ACC circuit, and the red one is the one that go to a always on circuit.
The piggy back fuse adapters, the bottom slot is the one for the fuse you piggyback on, the top one are for the new circuit you make, and a 5A fuse will be just fine for that.
As your car is a 2017 one it could have some smarts in the power system, this can make it hard to determine what fuses are actually the best ones to use, unlike my cheap 2012 bottom of the barrel Suzuki car, which have no smarts what so ever aside for its driver.
Most often this is the ACC wire that is hard to figure out a good fuse to tab into.
Viofo did have some issues with some parking modes on a model but unsure if the 129 pro duo was it, as i recall it was just one of the modes and others work fine.
Personally on the camera i use parking guard on i use always record low bitrate and then i have the G sensor on too, and use a 1 hour cut off as i dont really need parking guard other than when i am shopping.
It sound odd you would have the same problem with 2 different systems, you shouldent by any chance be using the same fuses to tab into for both systems. ?