Is there anything wrong with this particular timer circuit utilizing 555?
Your concept (guessing here, because you have not precisely explained what you expect to happen) appears to be wrong- opening the ground on the x1117 will not give you 0V, it will give you almost the input voltage. 

When the MOSFET switches on it will drop to 5V. 

But your timer not working is another thing and may involve some issue with construction or some other difference between your breadboard and the PCB (including a fried chip, but that's probably unlikely without a bit of drama such as it getting very hot). 

Measure the voltages on each pin- pin 5 should measure about 2/3 Vcc and pins 2,4,8 should measure about Vcc. Make sure the rotary switch is wired correctly. And try triggering the timer by momentarily shorting C1.