Hi,
It seems you are in a quite a trouble and yours is quite a complicated case. Actaully NZQA checks one degree and transcript as one complete course.
So there could be 2 possible solutions.
1. If you can somehow manage to convince NZQA that your previous diplomas and this one year degree is one thing then may be you can have a desired outcome.
2. If your UK University can issue you a new transcript in which all the courses required for a 3 years degree are included then may be things can work out.
I really don't know that if above will workout or not but in my opinion you should first contact the UK University and see what they says about it.
Regards,