Minor service, MOTOR CEASED

I took my vehicle in for a MINOR service. Keeping in mind my vehicle is under 70000km. 3 days later my car broke down on the highway. I phoned in asking for the manager to come look at my car,they agreed something was wrong and took the vehicle back to Meadowdale branch. Confirmed that they did not tighten the sump plug after changing the oil filter and my motor ceased. Needless to say it has been an uphill battle. Two weeks later I receive a call saying I need to come fetch my car. I go speak to Phumlani and request the vehicle go to the agents for 62 point check to which he refuses and says I need to pay for the checks. After hours of debate with him and Vanessa from their head office and involving my insurance,they agree to take the car for the checks. IT FAILS. The car goes back to their branch for further inspection and repairs. 2 weeks later. I have heard nothing from them. Thursday they advise the vehicle will go for checks again. Today (Friday) I am called to collect the car as its "passed" the checks. I inform the owner of the company I can only collect on Monday as my assessor will be coming with to ensure that the vehicle is repaired to standard. Phumlani then refuses to extend my car hire for 2 additional days and screams at me over the phone. After being inconvenienced for a complete month due to their lack of detail. I am also being refused any paper work for my vehicle, invoices,parts replaced and repairs completed as they're starting that they cant disclose what they've done on MY vehicle. Vanessa from head office informed my insurance that we can take it up with the CEO of the company. I will be taking this to the ombudsmen. Completely unprofessional and ***********!!!