Ok I have tested this multiple times on Beginner mode.
Tried it only with Teemo, but the bush part should work on any champ.
Haven't tested it yet on intermediate.
Probably gonna test it later this night.
Picture removed because video was added.
Bug:
So you need a base, which is enemy controlled.
If there is no enemy at that base, go there and start capping it.
When you see enemy coming to defend it or take it back, go and hide.
Worked best when I used Teemo's Camouflage at marked spot with yellow X on picture, also I have tried it with the bush where I am hiding on this picture.
What happens is, Bots come to that base, and they are moving around it, but not leaving it.
Seems like they somehow sense that you are there, thats why they don't leave, but they can't attack you or see you, since your are hiding or camouflaged.
So what you do is, group up with friend, you do the trick and bug bots so they stay at one base, while your friends cap other bases. (mostly 2-4 bots stay at the base, never managed to get 5) and wait for win.
EDIT:
Here is the video: http://youtu.be/sYOyXn3rQO0
On the video you can see that I stand as Ashe in the bush down, and bots are bugged at the base. Swain left, because allied Volibear was near... but new one came and got bugged.
Enjoy.
Would be good to rep atleast if you are using it (I saw it in ULB bot using as Dominion WIN match), not just leech.