The are construction laborers
I was asking if you can do a certified payroll with contract laborers .
The answer is there is no such thing as Certified Payroll for vendors.
Contract Laborers are vendors and are not part of the payroll.
Your client's bigger issue will be dealing with TWC and IRS on employment tax issues, however. TWC will come down hard as soon as one unhappy worker files a complaint with TWC.
If your client has set up a corporation or an LLC taxed as a corporation, he MUST have at least one employee (himself), and that would then require certified payroll.
If he is a sole-proprietor, then he does not need to be on the payroll himself.