Glad to be of help
Mine was the HP pipe and the leak was minor so the system didn't run dry / out of fluid, so no damage.
Don't see why you cant crop the pipe and use a longer bit of hose for the LP / return pipe.
But the hoses are not that expensive so probably worth renewing both if one failed then you would see any tell tale metal particles when you drain the system if there is a bigger problem.
The black secondary air pipe is used so as part of the emissions control when a cold start i think, if it is holed the car would probably not idle very well or EML would come on.
The underside is quite thick where the metal is folded so unlikely that is holed