This is beyond insanity. Branding all the modules the same: XBee Pro, and they all use 900MHz frequency bands, and they all support DigiMesh, but they are not compatible with each other????
How on earth could the design group come up with such a thing? Did they seriously have this conversation: "We'll make two products under the same branding, with the same frequency and feature support, but we'll make them ***INCOMPATIBLE*** with each other!"
How could anyone think this is a "GOOD" design decision?
They could AT LEAST publish a compatibility matrix somewhere - like with all the XBee products! At this point, I have no idea which Digi PRO modules can be used with the others, and I have no idea how to find out. Is there an interoperability matrix that clarifies this?
Look at the comparison chart at the middle of this page: https://www.digi.com/products/embedded-systems/digi-xbee/digi-xbee-gateways/digi-xbee-sx-rf-modems#overview
You'll see the Digi Pro SX modems and Digi Pro 900HP modems have the SAME specs. HOW ARE WE SUPPOSED TO KNOW THEY DON'T WORK TOGETHER??? More importantly, WHY DON'T THEY WORK TOGETHER???????
They could also NAME THE PRODUCTS DIFFERENTLY so that we don't assume they're all part of the same interoperable family.