Consider a 14U match...
Blue 2 is a defender who is crossing the ball to Blue 3.
Blue 1, the keeper, steps forward and picks up the ball.
You blew the whistle when Blue 1 touched the ball.
Blue 1 glares over to you: "Incredible! Red 3 was all over me, I couldn't see anything and couldn't move. Now I get called?"
You hear "offsides" being said by a few sideline parents and Blue coach.
Red coach is shouting to their midfield to move up for a Penalty Kick.
Your club linesman, a Red parent runs on to the field and tells you Red 3 was offside.
Play is stopped, both teams are becoming restless and looking to you.
I wouldn't go with impeding, as I don't see anyone in the scenario preventing another from playing the ball. My solution is as follows:
No pass back to the keeper because the angle is wrong. The keeper came out and got it. Might it be a set play? A clever coach might attempt it, but the risk of a pass across the face of their goal probably isn't worth it.
The whistle is incorrect. Since no infraction occurred, the restart is a drop ball. Since the keeper had possession, I would drop it to the keeper. I would also violate the literal reading of the LotG by declaring that I am dropping to the keeper. These are kids after all, not pros.