Sub-standard service

I took my car to Tygerberg Multifranchise for a major service about a month ago (they are an accredited Renault dealer). Today I took my car to another reputable service centre for the replacement of my timing belt. The technician showed me two other problems that should have been picked up at the service a month ago. One was the problem with Tie Rods, which have cause a play on the front wheels.. Why did Tygerberg MultiFranchise not pick this up? Really shoddy service. and this is not the first time. You cannot even complain to Renault SA, as the SA Distributor and the service Centre belongs to one parent (Imperial Holdings).!!. So much for Competition in SA...