I just wanted to follow up on this to confirm that all works as expected. I now have two different three way circuits setup with associations as described here, one with 2x LZW31-SN and the other with a LZW31-SN and LZW31.
By the way @EricM_Inovelli, given the discussion above and my experience the documentation here is misleading. Specifically this section:
Non-Synced LED Bars: The LED Bars will not be in sync with one another – this is more prominent on the dimmer as it will not show the correct level.
Honestly this was part of the reason that I held off on investing in any of the Inovelli switches. I’m glad to find out that it works as expected with the group 3/4 associations – I really hate mismatched switches.