The car shows as compliant on the
TFL ULEZ checker and also on the
gov.uk Clean Air Zones checker.
The DVLA would have assigned an unissued VRM to the car consistent with the reported date of 1st registration in it's country of origin. In this case this is said to be September 2013. So it's been issued with a 63 series VRM. So some proof of that date was likely supplied with the registration application.
In order to determine compliance the ULEZ and CAZ checkers will first look at the VRM. If it's later than Jan 1st 2006, then for a petrol car then it will assume the car is compliant. This is because it would not have been legal to register a new petrol non-compliant (with Euro 4) car on or after the 1st Jan 2006. At least that is the case with a UK market car, which is not the scenario here.
It looks like the actual emissions are not further checked for possible compliance unless the car doesn't pass the VRM check.
So does that mean that the DVLA will ignore Euro compliance for a non UK/EU car when it gets re-registered in the UK?
Or is it the case that that evidence of emissions have to be provided with the registration application? The rules seem to be very opaque.
And it seems that the Single Vehicle Approval test can be waived where the car is more that 10 years old.
In any event surely the MOT test centre would have to test the car to the same emissions standards that apply to the equivalent domestic model. Not to mention that Japanese emissions standards will be at least as stringent as the UK/EU standards and may even be tougher.
I suggest you go back to the dealer who sold the car. Ask them about what information and documentation they supplied to the DVLA to register the car? And what happened to the emissions info?
