Though I believe a push/pull type split would work well for an individual, I don't know why your telling him not to do any isolation movements?
Look, no one ever told him to FOCUS on them, but adding a few movements in at this period is critical. If he doesn't, he'll build a body thats not proportionate.
Likewise, adding isolation movements help to develop the mind muscle connection early on, which is IMHO, VERY important.
OP, a basic routine, like a push/pull split, upper/lower, whatever......will all work fine. Add in some isolation movements, as they are important.
Progression, consistency and effort are what you truly have to be worried about