Collision and base tagging

[Roman Konecny]

OBR (kids 10-12); Two out, R3; BR hits weak jumper between F3 and F4. F3 decided it was his job and make for it. Then turned back and noticing pitcher minding his job on mound runs to 1B. Step on 1B in the nick of time, so far so good, but his momentum brings him further and he collided with the BR just over 1B. F3 dropped the ball because of that collision at about a time when R3 has been celebrating winning run. BR was trying to avoid F3.
My rulling was safe, call it a game. You can imagine that defense manager has not been happy about it. I however somehow managed to leave the field with some degree of dignity ;-)

I based my rulling on:
6.05 A batter is out when (j) After a third strike or after he hits a fair ball, he or first base is tagged before he touches first base
2.00 A TAG is the action of a fielder in touching a base with his body while holding the ball securely and firmly in his hand or glove; ...
My rulling of 2.00 TAG in above case is that F3 has not been holding the ball securely. But I might be a bit WRONG on that.

I am an amateur umpires in europe and such as I have not much materials to study cases but OBR.
I had several discussion about above case with local 'more expirienced' umpires, but the decision they gave me was split to about half to half for safe/out.

Please gime me your oppinion on this play. Thanks. Sorry for my funny english.