WOW, WOW. WOW… Thank you so much, this works perfectly. Fortunately since I only have one set of phones that need to ring for all my queues I can actually have just one secondary queue q350 with the agents and all my primary queues q380, q381, q390, q391 (which are language and time conditions dependent) have q350 set as as the only agent. Everything works as you described with the MoH being updated as the caller is whisked through q350 straight to an agent.
It might be a little messy, but gives a great customer experience to the caller since we can rescue them from a queue without having to wait for announcements to be made.