Pod, many internet sites allow free use for commercial or private. And Mayang's license does also.
Quote: "License
These textures are Copyright © Mayang Murni Adnin, 2001-2006. They have all been taken by our own cameras or created by ourselves.
Use:
They are free to use for all uses, whether commercial or non-commercial (you may incorporate them into your derived work with no requirement to pay us any licensing fee etc). Your derived work must involve significant modification(can mean as much as croping the image portion out you want to use. I've already emailed them on this. As long as it isn't in it's original form) to the textures. It would be nice if you could credit us.
Sell:
You may not sell any of these textures in an unmodified form, or any derived works where the product you are selling is still a texture and is likely to compete with this website.
Redistribute:
You may redistribute (give/send to somebody else/display on a web site) up to 30 of these textures together, but no more. You must credit this website as the original source (tell them about us)."
http://www.imageafter.com/terms.php Has a very similar license.
Point isn't if he got them from this site. The point is they are poorly done for a commercial pack. Free I can get, but he needs allot of UV mapping experience before he tries selling anything. It's OK work for a "Here's my first model" kinda gig. But far from anything worth paying for.
Please don't let this discourage you theboss. We all start somewhere, and the fact you got them in game puts you light years ahead of others.