A Tinderbox of your Own III is a reward for getting reputation rank 22 with the Hallowfall Arathi.
It is a Warband reward so it should be available to any (lvl 80) character in my warband. It says "Speak to a Mysterious Child to start a quest for the Darkened Tinderbox (item level 597)
I went to Mereldar with a lvl 80 character I want the necklace on after achieving rep level 22, and i do not see any Mysterious Child.
I DO however see the child on a different character I do NOT want the necklace on, because they already have a better necklace.
The description makes NO mention of any other requirements for getting this quest.
While this is true, I don’t necessarily think this is a ‘bug’ per se.
I was having the same issue (I didn’t even bother checking my main). Straight to the wowhead page and someone makes mention of a pre-requisite probably being required but no more info.
I did a little digging on my own and found out you do need to do 2 previous quest chains to unlock the 3rd quest chain or ‘Profane Tinderbox III’. They are actually the only one that will be marked on your map in full yellow (if you have selected to skip the storyline, if not I am not sure). This is not how I figured it out though, just something I noticed afterwards.
The quest chains are actually lists as ‘Neck 1’ ‘Neck 2’ and ‘Neck 3’ in wowhead - which gives a clue as to what you need to do.
The quest chains are as follows: Honor your Efforts, The Flame Within, Whispers from the Web
I don’t have a wowhead account but if anyone wanted to add this information please feel free.