If your neighbour really wants to grass the area, I would suggest buying seed from a specialist company. For information on seed mixes I use the following website, but I've never bought anything from them so can't comment on their products. I do find the information very useful though.
http://www.thegrassseedstore.co.uk/garden-lawn-seed-c-31.html

Yes, he needs to use a shade tolerant mix or else it won't flourish. You can grow your own turfs in seed trays if it's too shady for seeds to get established (and only a small area!).

You used to be able to buy seed called Shady Lawn from garden centres in boxes, can't remember who made it.

Thank to all of you, that really is of help. PM