The puppy pad in the crate was a mistake. And a pup can not go 6-7 hours without a break. By putting the pad in the crate you gave your pup "permission" to pee in there and kind of set things up so that your pup has no choice.
So start over, clean the crate thoroughly with a cleanser like Nature's Miracle and divide it so that he only has access to half. You may need to replace the bed as well. Now set your pup up for success, tether the pup to you and watch for signs that he needs to go. When your pup potties outside-praise, praise and treat. If you catch him beginning to piddle in the house, scoop him and put him outside and praise and treat.
Don't use potty pads unless you intend that he will always have that as an option. You can limit water before bedtime but I'd be reluctant to deny water while crated during the day.
Work on this when you are home and do find someone to give him a potty break during the day. It's not unreasonable to crate a grown housebroken dog for six or so hours but pups need to learn where to go and their little bladders can't physically hold urine for as long as an adult.