I think your going a bit crazy accusing the garage going on about vosa already, im not saying the garage didnt do anything but chill out first. What did it fail on MOT wise? what work did the garage carry out? Is it the first time its been driven in a while? Has the battery been disconnected, re-setting the ecu? Are a ignition leads connected well? what boost was it running? whats it boosting now? It could be a million and one things yet, dont always asume the worst.