As phoog says, you absolutely are allowed to transit through the US on the way to Canada on a Dutch passport, even if you arrive by air and leave by land. Dutch passport holders quality for VWP, which certainly permits that. You would need to get an ESTA.
However if you have a return ticket to the US, coming back more than 90 days later, it looks to the airline as if you intend to spend more than 90 days in the US, and they might be worried that US customs will turn you away on the basis of that. Since that would cost them money they might decline to board you.
The other issue is that the sequence:
- Transit through the US
- Go by land to Canada and spend more than 90 days there
- Drive back into the US and leave by air
looks like it is technically against VWP rules. Trips to Canada famously do not reset the VWP clock. However the truth is more nuanced, as the rule is really there only to prevent people misusing the VWP by making a 'visa run' to Canada to try and start a new 90 day period. I virtually guarantee that no CBP officer will turn you away from the US at stage 3, as long as you have some evidence of the length of time you have spent in Canada. People do this all the time.
So your main thing is to make sure that the airline is aware of the totality of your journey, and (if it is them telling you that you can't use VWP) get them to agree that you won't be prevented from boarding. If necessary, telling them that you are considering visiting a central American country in the middle should do the trick. If they really don't buy this, make separate bookings for the outward and return flight.
When you come back to the US at the end of your stay in Canada, make sure you have handy enough documentation to show you have been in Canada for a long time, and your ticket out of the US. This should easily be enough to get you into the US a second time.
If for some reason you don't want to do the above, or don't trust the system, there is also no problem with using multiple passports on the trip. Just show whichever one gets you into whichever country you are entering. NZ and Netherlands both qualify for VWP. Make sure your ESTA matches the passport you will be using for the US.
EDIT: It's just occurred to me that you might not be able to get an ESTA on your Dutch passport because you already have a visa on your NZ passport. Visa holders don't need, and therefore can't get, an ESTA. If that's the case, then you'll have to use your NZ passport to enter the US. Still not a problem.
EDIT: We have other questions dealing with multiple passports. It's not a problem. Enter your NZ passport, with the US visa, as info for your flight. Show it as you board, and at US customs. Show your Dutch passport with the Canadian visa s you enter Canada. Use your NZ passport to return to the US and to board your flight home.