I shared this experience to create awareness not to judge fault.
You're right, that's the way to go. Accidents as this one shouldn't happen, if they do, they must serve to others as a warning.
I think the manufacturer of the light acted somewhat irresponsible in assuming that customers know about the potential dangers of such a bunch of high capacity li-ions sticked together. There should be a warning paper included with the light where the correct procedure to handle the cells and the light are explained, the dangers as well.
I began with li-ions only two months ago and I was glad I already knew that dangers exist and so I searched CPF up and down for detailed explanations. I restrict li-ion use to singles, I don't even put 2 x RCR123 in a light, if I need more than one cell, I take primaries or IMR. I wonder if you can feed the TK Monster with 8 x IMR? You loose over half the capacity, but to my understanding you avoid dangers as well.
Olight developped a battery-pack for their SR-90, as they were afraid to see such accidents happen. The battery pack, similar to a laptop or a cell phone battery, makes sure the cells are always well balanced and it is much easier to charge. That isn't possible for custom lights however...
If this happened to me, I wonder if I would have let the light fall on the floor? For sure, that was the only right thing to do, saved you from being really injured. It's not easy to do however, if you hold a brand new and expensive light in your hand!
A few weeks ago, a young man (not a juvenile fool however) died here after an accident with a firework rocket on new years eve. I don't know what sort of rocket it was and what exactly happened, as press didn't speak about an illegal item (reserved for professionnal use) I suppose it was a legal one as they are sold for such occasions and which are considered somewhat safe. I wonder what has more explosive energy, an 18650 or a legal firework rocket?
Stay safe with your rechargeables everybody!