Hi Adrian,
No 1 pic above, possibly. No 2 pic above
Absolutely not !
What I will mention for info is that my camera is also a Nikon with the same sensor size as yours, older technology with less pixels than yours. I say this because anything I can produce (quality wise) with my camera you can also produce with yours if you have the right lens.
Now to try and explain the answer to your question without figures
I also have 70 to 300mm lens (as Geoff mentions above) in addition to my 1:1 macros but mine also has a special 'close focus' function that can be switched on that is a type of pseudo macro, instead of a true macro 1:1 ratio, it has half the magnification at 1:2.
Here's a quick example I just did of a fly (sorry it's dead but I knew there was a reason I was leaving it on the bedroom curtain) which is exactly 20 mm overall length. Ignore the way out WB as I used flash to attempt to get a reasonably sharp image due to the distance I was shooting from.
No 1 - Taken with the lens in its normal mode at 300mm FL
No 2 - Taken with the lens in it 'macro' mode 1:2 magnification at 185mm FL
No 3 - Taken with the lens in it 'macro' mode 1:2 magnification at 300mm FL
Would any of the above meet the sort of standards you are looking for?
I would be interested to know why you have decided against going for the macro lens as originally discussed?
Grahame