If I didn't leave water in the crate, I would be giving the pup a drink immediately after coming in from the first morning outing, the sitter would give a drink and then we'd let the pup have water when we got home (probably pick the water up after a certain hour at night though).
I've never restricted water, but there are many that do. What happens if something comes up after work and you're even later that you usually are? I couldn't stand it if I knew my pup was without water. IDK, that's just me I guess. If you crate or use an x-pen, I would suggest a water bottle. They keep things cleaner, (no spilled water), and they're very easy to teach the puppy how to use them.
If you're planning to have the sitter come in only once a day you will
have accidents, there's no way around that. It's been awhile since I had a puppy, but I do remember taking them out at least every hour or two, maybe more. I would have the sitter come at least
two to three times a day during the first few weeks just to avoid accidents as much as possible.
Also, having just a light breakfast and then only a snack during the day, I would think your pup would be starving by the time you came home. Again, it's been awhile since I had a puppy, but that doesn't sound like an optimal feeding schedule to me. At that age, all
the meals are main meals, especially to a growing puppy.