Ride clutchless or, if you don't feel confident/even know about it USE THE FUCKING BREAKDOWN - THAT is why you bloody well paid for it in the first place!!
You don't think they could manage to reach you on busy town roads or something?
Fuck, just pull up on the nearest pavement, brake to a stall, park up and walk to the fucking garage or even catch a taxi, as you're in the busy part of a town.
Buy a cable, walk back, swap them out and be off. Failing that, call your mum or a friend and have them go get you a cable while you guard your bike...
That was seriously fucking stupid and anyone doing the same will get no sympathy here.