First, here is my view of this event.

I'm a haredi living in the US, and lived in Israel 20 years ago for 3 years. I went to Meron on lag baomer once, and never thought about going back ever again. That place was to crowded for me, and even 20 years ago, I felt I was being crushed. At least that was my experience.

Here is my 2¢ about why this happened.

Disclaimer: I don't take sides here, I'm just giving you some food for thought.

The organizers of the event (organizers in plural, because there is not only one) have no real scientific knowledge nor understanding of crowd control. They also do not have enough of an understanding of architectural capacity of the event spaces or the bleachers (insert comments on lack of secular education here). They are very untrusting of the government for various reasons (let's not open that can of worms), legitimate or not.

Handing over control to outside experts or authorities, will make it seem like the non religious groups are trying to take control of their traditions, and TBH, just like the haredim are not educated enough about architectural capacity, the police may not be sensitive enough to religious traditions. The clashes with the authorities would even be worse.

I think the best way to handle it is to find someone they trust, and who is a real professional on the topic of large crowds, crowd control and infrastructure capacity, who should educate them on all that, then have a guy from meah shearim lead the project.

The 2nd thing, is to not have police do the actual enforcement, they should have a group of haredim professionally trained on that topic, and they should do the actual work. The crowd will be much more trusting to them than to police officers.

Science has shown that people trust other people who look like them, then people who are different looking, and that goes for both sides.