I hesitate to argue with a National Panel ref, but:
Was the hooker on the line of touch?
Was the throw in straight?
Did the throwing in side have 2 (or more) participants in the correct position?
Was everyone else from the throwing in side back 10?
If yes to all the above, I don't see why not award it. There is no requirement in law to wait til the opposition are ready.
The QTI was not on - the ball-boy touching the ball is the reason for that.
It looks from the answers given by damo to your questions above that many of the throwing-in team were offside.
Assuming however that the throwing in-side had two line-out players at the line of touch, and the rest of the team was onside; why would not 19.2:
[LAWS](a) A player may take a quick throw-in without waiting for a lineout to form.[/LAWS]
followed by a list of conditions (in (b), (c) and (d)) to be satisfied for the QTI to be legal, not mean that if the QTI isn't on, the throwing in team
must wait for the lineout to form. If they throw in before then, they are attempting a QTI without satisfying the conditions making a QTI legal.
Law 19.8:
[LAWS](a)
Minimum. At least two players from each team must form a lineout. [/LAWS]
[LAWS](d) When the ball is in touch, every player who approaches the line of touch is presumed to do so to form a lineout.
Players who approach the line of touch must do so without delay....[/LAWS]
[LAWS](g)
Failure to form a lineout. A team must not voluntarily fail to form a lineout.[/LAWS]
all sanctioned by a 15m FK, between them deal with the other team being slow about getting to the LoT.
Or, to put it another way - there may not be a requirement in law to wait till the opposition are ready - but
any throw in before the lineout is formed is by definition a QTI, and there is a prohibition in law against taking a QTI with a ball that has touched someone else - so in this instance the throwing in team had to wait for the lineout to form (or for the ref to sanction the other side for delay).