If he is looking at gaining I don't know I would even bother with Zone at all. It sounds like he doesn't even do the basics of nutrition and the milk part isn't necessary it just helps a lot.
I mean he needs to start eating at least a base amount of calories before even considering the milk option anyway. The milk thing is in addition to everything else. I'd first get him eating just MORE and then worry about adding more calories. SS is great and if he is a noob he'll make great progress with it doing exactly as it's laid out.
Protein - At least 1 BW in grams
Carbs - At least 1.5 BW in grams - I'm guessing he doesn't have a problem with carbs since you didn't mention it.
Fat - At least with 1/2 BW in grams
That adds up to (2.5 * 133 *4) + (66 * 9) = ~2000 calories Then work up more fat with stuff like coconut milk, nut butters....etc
"And for crying out loud. Don't go into the pain cave. I can't stress this enough. Your Totem Animal won't be in there to help you. You'll be on your own. The Pain Cave is for cowards.
Pain is your companion, don't go hide from it."