Just read this topic about AIG.
I agree with the above comments and I agree. Especially regarding the fact that "Anyone can set up a gem lab. No qualifications or expertise are required.".
Here I write you my personal experience.
I was interested in certifying jewellery and loose stones, therefore I contacted different labs asking for quotations and more insights. Among the other I called AIG Milan Laboratories which is the italian branch of AIG and IGL laboratories in Israel. Well, I was really shocked when I learned that AIG Laboratories write on their certificates what the client asks for, even avoiding to mention treatments and declaring the grading on client requires!
Personally, I defenetely wouldn't trust a lab which gave me the impression of a printing center. I would suggest you to check reviews on impartial websites as certification field is getting a jungle lately