They will send you a waiver form to fill out in lieu of any certification. Their only concern (and rightfully so) is that they are indemnified from any liability in case you do something stupid. It doesn't require a 107 cert but they will take it. I don't blame them. In this litigious society (especially in California) people sue manufacturers for things done with their products. You've heard the saying "Guns don't kill people, people kill people". Well there will be someone who will sue a gun maker saying, yes, but if the gun didn't exist, that person would still be alive. Even frivolous lawsuits cost companies millions.
But, again, just to be clear, a part 107 cert isn't required. Just fill out a waiver form that they will email you if you ask.