Btw as much as I loathe Djindji's opening works, in this case I think he can be excused for not mentioning it: 7.Bc4 has never been played in my database.

I'm at work so I can't check this analysis with my computer (and thus may be overlooking some tactics) but after 1. e4 c5 2. Nf3 g6 3. d4 cxd4 4. Qxd4 Nf6 5. e5 Nc6 6. Qa4 Nd5 7. Bc4

A) 7...Nc7? 8. Ng5! looks rather uncomfortable for black (eg. 8...e6 9. Ne4! and black's position becomes very cramped).

B) I think 7...Nb6! is definitely the way to go. After 8. Qb3 Nxc4 (not 8...Na5?? 9. Bxf7 mate) 9. Qxc4 Bg7 black's pressure on e5-pawn is at least enough to equalize.

Hope this helps 

Some stuff on this in the Alburt, Djinji, Perelshetyn book. Opening Rep for Black.

As Watson notes in a review of their Opening Rep for White book, a lack of integrity on the part of the authors is clearly apparent. Had already noticed that myself when comparing theory from various texts and with my own experience. 
That said, texts are worthy as an overview. Some good explanations. But certainly not to be trusted overall as they have a knack of avoiding lines that prove troublesome. 

Bibs