Hello!

I have no data bout the prices of Command Flags in events but I would like to give a suggestion which I personally do. I don't spend for Command Flags since I do value my coupons and want to spend it where I can get the best of it. What I'm doing or what I did with my account is, I do always claim these Optional Packs where you can choose between 5 Command Flag Fragments, Training Potions, and the pills for upgrading the card's effect. I believe every week has an event where you can claim this pack for free using the points that you can get from doing missions or such. It is a bit slow process but surely you'll get one for free.

Now for the two events that you mentioned above, Outlets would definitely give a lower price since it is a direct purchase but gives a little to nothing in return. While on the Konoha Great Tree, it involves RNG for the number of points that you can get from using the Dews with minimal value of return from the items that you can get from the tree itself.

I hope someone can share data of their spending for this matter and I do hope you find the best way to get Command Flags from the events. Thank you.