The subject matter might be on topic, but it is not an answerable question because it is way too broad, so is likely to be closed. The premise seems to be that these people have magic powers whereby anyone will grant their request when asked in person (if people have free will can can oppose the bill, as is the case in reality, you would have to know exactly which persons oppose the law and you would have to know that the monarch and responsible minister support the law).
The primary question is, what law(s) of the Netherlands need to be changed to allow this one organization to exceptionally use police sirens (and be legally treated "like police with sirens running") as they see fit. Simply determining what the actual set of laws is is a huge question.
The secondary question is about how laws come into existence in the Netherlands (who has to approve and how), and do you have to add extra people to the count to pass whatever consistency filter there is w.r.t. EU law. The tertiary question is whether this could be a secret law, under Nederlandse law, because if it isnt, that defeats the purpose of secrecy.
Finally, given the premise that they can "persuade" people that they talk to simply by saying "Do this", the number of people that they have to talk to is functionally irrelevant, because they can command people to do without knowing what they are doing.
My point is that without more detail of exactly what you want (and given that this isn't necessarily constrained by reality), the question is literally unanswerable because there are infinitely many scenarios that we could imagine. There are some addressable and real questions, but it's not clear to me whether the second question about the political structure of The Netherlands is on topic for Law as opposed to Politics.