If You Had A Twin, But Didn't Realise...
Family Life15 mins ago
No best answer has yet been selected by pal. Once a best answer has been selected, it will be shown here.
For more on marking an answer as the "Best Answer", please visit our FAQ.Who fitted the cambelt?
The cambelt could have been damaged or something on the engine could have been touching the belt (e.g. cover) and damaged it enough to break.
Additionally the belt could have been put on with the incorrect tension - either too tight or too loose would cause damage to the belt.
Agree with kebabmeister - the garage certainly have some liability. Are you a member of a motoring organisation ? If so, get in touch as they should have a legal department for advice about such matters. Failing that try the CAB or your local Trading Standards (part of local Council) for advice.
Good luck !