Depends whether or not this is Goku at the start of the arc, or during his battle with Si Xing Long and onwards. If it's the former, he gets stomped and if the latter, he stomps seeing as how he's implied to not be too much weaker than his SS4 form. For scenario 2, Goku would stomp with SSJ.
Kaio (Ultimate Butoden) VS Power Weighted Perfect Cell
- In this game, Kaio was able to beat LSSJ

without seemingly any difficulty. Assume this was Movie 8 Broly.
- If Kaio wins, have Cell go into his Super Perfect form.
- If SPC wins, have Kaio be backed up by BT3 What If M8 Roshi who did the same feat as Kaio.