That was handy, shame about the other bike, would have been useful. If I do again, I'd probably chance it and see, though it would be in bits in the back of the car! NOVA says you have 14 days so it shouldn't have to be done at the border in theory but you know what officials at those places can be like.
Interested to see how you get on with a Dutch registration in your name. In Holland generally the process is similar to here for export, but you take the Reg Doc to an office to tell them it is exported which is what Lex did for me with the X7 and you get the Exported registration paperwork (the TZR250 was the same). The equivalent of doing the export option on the V5 here) which I am guessing you can't do now? That takes it off the dutch system else they'll always be contacting you if they need info about the bike? Or is that what Lex actually did?
I had to deal with HRMC CARS in Belfast with the TZR and I would suggest phoning them if you haven't:
HMRC CARS team
ecsm.nchcars@hmrc.gov.uk
Telephone: 0300 322 7071
They were really helpful the times I have talked to them. You'll have to send off the paperwork to them and they will assess the VAT liability and let you know. I initially sent off the TZR via post but hadn't heard from them for a week so called them and they said email it, it's more efficient as mail goes around the houses, has to be scanned in etc and takes a while. I emailed it off the Thursday evening and the NOVA was back on the Monday (was in EU then so no VAT to worry about).
Good luck.
UB