The advantage to hiring a licensed contractor (versus a usually cheaper handyman) is they carry insurance.
You can check to see if his license is still active (google: Washington licensed contractor), although this won't give you his insurance information.
This would be a claim against his insurance. I believe you have a duty to offer him the opportunity to remedy the situation (this may be more than one e-mail/phone call). Ask for his insurance carrier from 2014.
Be specific in your request. Show the contractor the pictures and have your other contractor write up a statement about the cause of the damage. It's unclear to me where this box is (on the roof or the side of the house?).
Water mitigation is the number one callback for contractors.
This is a big deal. You don't want to have to start paying for hotel nights for your tenant. I would not delay in seeking a remedy, whatever that may be.
This may be a claim on your homeowner's policy and then let them go after the contractor (just a thought).
Can you tarp the roof for a temporary solution? If you give work to your contractor he may do this as a favor. This would resolve the emergency for a couple of days.