I agree with you it is a bit strange that when applying for a visa that let you stay over 90 days there is not a single instruction about the TM47 90 day reporting. I know there are some people telling everybody should know the law. In Hat Yai I could just walk in and tell I had to do 90 day reporting. 5 minutes later I was outside again. What I needed was TM30, copy passport entry stamp, copy passport personal details, copy visa and filmeditie in TM47 form. I got the filmeditie in TM47 form by applying online first, sometimes that seems to work even for the first time, but it also gives you filled in TM47.
it is all about timing. If you want to stay maximum of 180 days, best do first 90 day report a bit too late within the grace period, then the next one needed is after
Just book a flight you can cancel. When the visa is rejected, cancel the flight. When the visa is approved, decide if it is better to cancel and book cheaper flight or just use the booked flight.
Leave on day 89 and you do not need 90 day reporting. You can keep doing that forever, but 90 day reporting is simple and free, and takes much less time than a borderrun
I do not see you litterally need to bring in everything. Proving you still comply is not that strange. And documents that are not time dependant you still have, so what is the difficulty? Showing your soft power is still going on, or your still work remote is not that difficult. Show online you still have 500K is also easy.
After deregistering from Netherlands, you cannot apply for DTV from Netherlands I think, so then you should apply from another country. Is there a reason why you want to deregister?