I just buy cheap meters for China like the DT830 only because the postal delivery here is hit and miss. I could buy something used like a Fluke but these aren't all that cutting edge like the Aneg multi meters. What is interesting is what is the difference aside from the obvious between say a neon bulb and a GDT except one is a safety device and one is just an indicator. They both work in similar ways. So... just for fun suppose you tried to swap the GDT for a neon bulb. How would it work? Would it actually ground a low power surge say from a static discharge or not. After all you can get 20 of these things for less that 4 dollars on line. I bet they would work for Joe Smiths grill starter test.
So when I suggest buying a better meter, you would rather buy cheap ones and keep replacing them. I assume that has not worked out so well for you and replacing meters has become too costly. Rather than buy a better class of meter, you want to try to modify one with a $0.10 neon bulb to save money. For now, let's forget about the cost and Darwin awards.
One thing about a GDT, they will not stop conducting until the current drops to basically nothing. You put DC across it and if the tube fires it will basically short out the supply. The MOV will act more like a zener. You could put a MOV in series with a GDT to get the reset and higher voltages. I've tested a meter that was designed like this. One thing I have yet to test is a handhel meter where they have placed a clamping device (GDT, MOV or neon buld) directly across the inputs. There is always a PTC or something there to limit the current. Even with the cheap ANENG meters you mention.
The ANENG meter is a bit special in that they actually do have a clamp right across the inputs. It's called the rotary switch. You may feel these meters are cutting edge. I say they have set back the front end designs to the stone ages..
The grill starter is a very short high voltage transient. Everything is done and over in under 10ns. The peak current is much lower than the standards call for. Hard to say if the neon bulb would do anything for it or not. Same for putting a MOV across it.
You are damaging your meters with some sort of magnetic choke field collapse. I suspect this transient will have a longer decay, slower rise time, potentially much higher energy and a much lower peak voltage. I mention this because it sounds like you may feel that if it survives the grill starter, it would survive what ever you are doing. This may not be true.
Show me what the setup that damaged your 830 and I will get a couple of 830s, attempt to replicate your test, install a neon bulb in the second meter and see if it then survives. If it does, we will try the piezo grill starter. If it survives that, I will use the ESD gun I designed. If all of that survives, we can try the other generators. Maybe finish the job with that half cycle simulator. This is what happens to a light bulb when placed across it. Second video talks about MOVs and GDTs.
https://youtu.be/ms5OIBnQ_ig?t=17 https://youtu.be/wYCGnYglRjY