Sound insulation between rooms with suspended ceiling

Normal panels come below that. No acoustic ceiling.

Then the sound insulation provided by the wool is absolutely sufficient.

Are there specific types of wool that are recommended for this? And then just "pinched" into the gap to the ceiling?

I do not see such significant differences after the comma that you should prescribe a specific product to the executor.

So, in my old office, there was a tiny gap (about 5mm) between the drywall panels and the exterior wall, and we could overhear every conversation from the neighboring office. Whether and how much insulation wool was in there, I couldn't see. But on the other neighboring office, which also had a drywall partition, there was no gap, and I could never hear anything. I would insist that the gap be sealed with something so that there is no "air connection." Whether acrylic or silicone is the right choice, or cord, or even expanding foam, I don't know. But I would want it to be airtight.

I don't see such big differences after the comma that you should prescribe a specific product to the performer.

Well, I would prefer to just do it myself. It's not rocket science to stuff the wool in, right? ;)