Why would you not want to use Marketo's deduping capabilities in this case?
Website>Marketo>NetSuite is the preferred method.
This gives you options to clean, append, and do other things before the lead even hits NetSuite.
If you go through NetSuite to Marketo, Marketo won't dedupe, so you'll need a NetSuite tool or a RingLead in Marketo to process the leads anyway. You'll also clutter your CRM with potentially bad leads that shouldn't go to Sales at all (or for a while). I imagine NetSuite allows you to route leads and to hold them in Queues or something too, but that should be the end point after Marketo.
So the real question is why does your "team" want to do the opposite of a standard Marketo setup? Is there a compelling reason to make this harder?