Audio sharing with Amazon Music Unlimited

I have a pair of Airpods Max headphones and a pair of Beats Solo 3 headphones. I listen to music primarily on my iPhone 13 mini using the latest iOS. If I'm listening to the Apple Music app on my phone, I can easily share the audio output on both sets of headphones using the recommended method to share audio. No problem.

But, here's where I do have a problem when using the Amazon Music Unlimited app on my phone. I start off using my Airpods Max in the usual manner. When I try adding in the Beats Solo 3 using the same sharing technique that I use when listening with the Apple Music app, after the Beats Solo 3 connects it knock the Airpods Max off the stream and in fact the settings menus show that the audio is only coming out of the phone's speakers.

So, my question is whether or not the Amazon Music Unlimited app supports sharing among various Apple headphones/airpods. I would contact Amazon support, but I've found them to be just about worthless over the years.

If someone out there can answer this question I'd be grateful for the help.

StewCal