I have driven my rapid for 350kms at avg of 130km/h i observed a gasket tear at downside what to do ?

Your 350km drive is unlikely to have done this - probably failing for some time. A good exhaust specialist will find and fit the correct flexi repair section. Tempting to get creative with fencing / baling wire but unlikely to pass inspections or last.

 

Worth also checking your engine mounts for excessive slackness allowing excessive movement.

Well you are missing an entire underside plastic cover so it's likely you just hit something