Okay, I realize I am about to voice an unpopular position, so I have already assumed the ducking position. (But should I
kneel in order to duck or
stand and duck? I still haven’t decided.

)
We should start with the passage from the GIRM in question. Here is what GIRM 160 says (in part; emphasis added):
I should say, first off, that I fully understand the desire to kneel to receive Communion. I sincerely wish that
that was the norm (and it may soon be). And, of course, the Eucharist should
never be denied to someone who kneels (nor should they receive even the
threat of denial).
However, for whatever reason in the United States, the
norm is to stand while we receive Communion. If the Pope is making it standard to kneel for the reception of the Eucharist at the papal liturgies, well that is certainly his right. Perhaps that means that a change is coming. But the fact remains,
we are not there yet, at least not in the U.S.
All the GIRM says is that the norm is standing. There is no little asterisk saying that people may also kneel if they wish. All that is said is that they shouldn’t be
denied for kneeling. These are two
very different things. Of course the Church is not in the practice of denying Communion to anyone based solely on posture. That would be quite silly. But I find it very telling that the GIRM does
not say something like
“People may kneel for the reception of Holy Communion if they wish” or
“The local bishop may make an exception for his diocese by allowing people to kneel for the reception of Holy Communion.” Nothing of the sort is stated.
Further, it goes on to say that instances where people kneel
should be addressed pastorally, providing those who kneel with catechesis on why standing is the norm. Thus, the GIRM
asks priests to confront those who kneel and explain to them the norm. So no one should feel offended if the priests asks to speak with them after Mass. They are just following the GIRM.
Now, is it the place of the Youth Minister to do this? I don’t know. Maybe the pastor asked him to. In any case, by virtue of his position (appointed by the pastor), the Youth Minister is (in part) responsible for the catechesis of the youth of the parish. The fact that the OP works for him indicates that the OP is also in a leadership position (not to mention the fact that the Youth Minister is responsible for those who work under him). As such, I find it reasonable for the Youth Minister to expect that the OP respect and follow the norms established by the bishops.
Do some priests take it too far by threatening to deny Communion, or by inappropriately confronting the person about it
during Mass? Sure. And they shouldn’t do that. But it is their right, nay, their
duty as a pastor to ask that their parishioners follow the norms established in the GIRM.
In my mind, the real issue here** is fidelity** to those who have legitimate authority over us. What a great example we can be to those around us by saying, “Yes, I believe it is more proper to kneel to receive Our Lord in the Eucharist. But I humbly submit myself to the norms established by my local bishops, because their authority comes
from Christ, and my obedience to them is obedience to Christ.” I believe that
that is what we are called to do.