Is it viable? Having an argument about this...

So I go either WW or Lee Sin. I stay in bush near the bottom small minions(I have smite btw). I smite the big wraith and kill all the others. then I proceed to go lane bot until it's up again.

When both of us are level 3, we both die in lane, and he blames me for taking cs while he was dying, I only was walking to take 1 cs and then when the enemy jumped on him, I then tried to help and died. He told me not to jungle, and we start arguing about it...

So basically is soft jungling viable in 3v3?

Sure it is. But in my opinion, start in the jungle and when you need to lane, lane. Don't feel any shame for taking lane CS for even a few levels. It is rough in the jungle for the first few levels, and a constant flow of cs is something that could spark you up to get in the jungle again.

its viable but i think you got to be with people you know so the other person bot can play differently me and two friends do it sometimes

I disagree w/ going jungle/soft-lane which sounds like what you're describing. Go lane/soft-jungle. Either stay the heck out of the lane except for pressure-relief/ganks, so that your 1v2 lane can get enough gold/xp to compete, or stay in lane and keep it a fair fight. With someone like lee, however, you can easily be full-time laning and part-time jungling, without leaving your lanemate out to dry.

there is no point in taking smite if you dont stay in jungle the whole time,
its worth having the exhaust / ignite late game if you arent even going to use the smite to jungle full time
just wait til you get a madreds in lane then jungle full time, easy
the thing about the soft jungle is that you are depriving exp from your teammate then leaving him to 2v1 vs people his own level, thats not easy if you dont have the right comp
honestly dont both soft jungling with bot, just go all out jungle top and get fb gank lvl 2, easy win