Yeah, I experienced the similar issue . I sent my Honda city for Clutch Plate and Pressure Plate changing and once it was done then mechanic handed over to me the broken connector of Oxygen sensor. Which basically he has broken it during installation and later I had to drive for six months without the oxygen sensor connected and later bough the new connector from scrap yard and got the issue resolved.
Second scenario is related to Liana, the vehicle in question. If he has still not opened Throttle body then problem can be resolved by cross checking the accelerator cable near throttle body and maybe it gets stuck over there and unnecessarily pulls the throttle plate.
If he has opened the throttle body for servicing then cross check the cables first for sticking and second check the position of throttle positioning sensor. Normally playing around with TPS sensor or readjusting its positions resolves the issue with high acceleration.
Last of all, oxygen sensors connector could be broken which he must has installed it in wrong way. Check for head gas kit failure as precaution.
Whatever he says, you don?t need injector cleaning, tappet settings, only thing needed is throttle body servicing and test to see if oxygen sensor is attached properly or not.