There are a few area's to consider when the engine won't start.

My thought right off the bat is, how old is the fuel that you using at home? What nitro % is the fuel it was broke in at, and what % you have at home, and what % did they use at the shop?

Pull start or start box?

If the fuel is not getting to the engine, put your finger over the exhaust and starting it, that will force the fuel to the engine. after the fuel gets there, take your finger off.

I would say dump the fuel. Buy some new fuel with the right nitro % and prime the engine, and it should start.