You have overcooked the seasoning. I have done this once or twice too. Especially smooth surfaces (e.g. carbon steel) are very prone to this problem, unlike rough cast iron.
What you want is not a dark layer. The layer will darken with time and start looking like usual. But on a freshly seasoned metal utensil, the layer should be yellow-brownish. The stove may be too hot for this, especially a gas stove, I do my pans in the oven, for maybe an hour at 200 Celsius or somewhat lower. A burner under thin metal can cause hot spots of much higher local temperature, where the oil chars instead of polymerising.
There is also the type of oil you use. Generally, unsaturated oils polymerise easiest, but the final layer stays somewhat sticky. Saturated fat can give you some more trouble, but will have a smoother finish. I do multiple layers, starting with 1-2 layers of flaxseed oil - this gives a good basis, it is so unsaturated it can practically dry out by itself in the air - and finishing with cocos fat or lard, again 1 or 2 layers. For the first few time in a new pan, I try to fry with saturated fat too, for your wok you will probably find that the taste of cocos fat has a good harmony with Asian dishes.
And a word to the cleaning before: Vinegar was not such a good idea. Woks are made from reactive metals (that's why they need seasoning) and metals react with acid. Using acid to clean naked reactive metal will result in invisibly small pockets of reaction products on the surface of the wok, mostly rust. You can do this as an early step in cleaning, but afterwards you have to use something to make sure you have removed this too. To peel off the seasoning before reseasoning, you are much better off using a base, as it does not react with the metal. This will ensure that the new seasoning sticks to the metal itself and not to impurities which can be dislodged over time.
I don't think there is anything wrong with the wok. Chinese wok cooking requires some seriously high heat, if it was really too hot, you'd be complaining of the oil smoking so much that your eyes sting, or even seeing the wok bottom glow if the kitchen is somewhat dim.
The more probable explanation is that, as you are not accustomed to this type of cooking, you did not know that the garlic will burn so quickly. I would suggest that you go through the options in the answer to this question about burning garlic (it's a known issue when you use high heat frying) or start with easier recipes.
Best Answer
It can be safe - people use gas burning stoves inside on a regular basis.
The one thing you must do is ensure that there is adequate air-flow in your kitchen so as to prevent the build-up of carbon monoxide. This is as simple as leaving a window partially open when cooking.
Another concern would be how stable one of these is on your bench/work surface. Placing a large pan on top of a small foot-print stove will make it decidedly top heavy, so you should get one that is either low and flat (much like a regular cooking stove in a kitchen; e.g. this one) or one with feet that limit the movement/tipping capacity (e.g. this one). I have no affiliation with either product and make no claims about their ability to cook things, other than that MSR is a reliable outdoors brand. After all, you don't want your cooker to tip over and set your kitchen on fire or cause you to get burned from the hot food/pan and/or from the flame.