Well I think that answers the question.
You found the results of ejuicemeup shall we say a bit dubious, so you fiddled about with other settings until you got an answer that agreed with how much water you already knew to add to get 5% (5ml) for a VG blend with 5% dilution. Then fiddled it again with 3%. So as I said the calculator is fine for most stuff, but falls over with water, or alcohol added.
That is why I took the time to do my own spreadsheet calculation.
My base mixes are simple now, as I know I like 10% water I buy Aqueus VG that already has 10% water added in the lab (you can buy it with 20% water). So all I do is take a 100ml bottle of that, and add enough flavour to make the flavouring 20% of the total, simples.
This viscosity liquid for me is universal, it wicks fine in any of my tanks with stock coils (0.3 to 1.8 ohm)
in my rebuildable tanks at 0.2 to 0.3 ohm, and in my newly purchased dripper at 0.3 ohms.
So I don't understand why you say it will be to thin, and may piss through your coils, I have been doing this for over 6 months now no problem.
If I remember correctly my PG intolerant friend uses 15% water, but that is with VG, VG nic, and VG flavours.