1.6 ecoboost major issues

Hi all, just signed up here and posting on here on behalf of my brother who is losing the will, so any help appreciated.

Few weeks back it dropped cylinder 4, coil pack replaced as a generic reader picked up a cylinder 4 misfire, the plug was also changed as it was a crappy burnt shade. This made no change at all but a loss of coolant was also noted, although there appears to be no mixture with oil. Suspecting a head gasket it got sent to a local garage. The guy down there knows this apparent 'ford tech' who called round for a look, he reckons the turbo is U/S and it has burnt valves on cylinder 4 causing the misfire, even determined this without pulling the head?? Tried having a quick search through various forums but I can't seem to find anything similar. Also the car apparently runs better with the boost pipe disconnected? We are quite technical ourselves just didn't have time to be playing around with it, and seen as it is a 2012 car at 36k it seems a bit extreme. Is there anything else that springs to anybodys mind to check?

Also the same 'ford tech' reckons that the ecoboost range do occassionally go into self destruct mode and its usually a new engine job, is someone trying to have our pants down here?

TIA