VW Polo 1.4 TDi 03 plate - P1556 fault immediately following accident - JKB

I have a VW Polo 1.4 TDI, 03 plate, it was running perfectly (good economy, good performance etc.) then it was involved in an accident affecting offside wing/headlight/door. Immediately after the accident the engine was running very poorly - sluggish acceleration, low power etc.. During repair diagnosed P1556 fault but insurer (Direct Line) refusing to accept that this is accident related and therefore refuse to fix the fault.

I find it unbelievable that this can be coincidental - the car was running perfectly immediately before and then badly immediately (not after 10 miles or 20 miles or 100 miles, immediately) after. Could an accident cause damage that results in this fault and if so what could the cause be? Or is it really coincidence?

VW Polo 1.4 TDi 03 plate - P1556 fault immediately following accident - injection doc

Negagative charge pressure, I would check all hoses and vacum pipes & EGR valve. You may find a pipe off or hole in a pipe. May be if its been parked a stuck EGR valve

VW Polo 1.4 TDi 03 plate - P1556 fault immediately following accident - JKB
Thx injection doc. I had a look at past posts and saw that this fault code can be related to vaccum hoses and turbos etc. but wondered whether the accident caused it, because if so I think Direct Line should be investigating the fault and paying for the fix - is this likely/possible, if so what fault is most likely cause considering the damage was to the front O/S wing?
VW Polo 1.4 TDi 03 plate - P1556 fault immediately following accident - JKB

Just to let you know the outcome - took the car to an independent VW specialist (C&R Enterprises in Nottingham) and it took them 10 minutes to locate and diagnose the problem - split intercooler and intercooler pipe located front offside - was accident related and Dirct Line have now conceded this - it's a pity they couldn't diagnose the problem themselves - I think the service Direct Line provided was poor to say the least - they happily returned a car to me that wasn't just unfixed - it was also dangerous to drive.

Needless to say I asked C&R to fix the car - and it's now running as it was before the accident.