Connecting just one wire (even to ground) may not be enough for Flux to recognize the module as mechanically part of the board assembly for STEP export. In Flux, the STEP export tends to include only those objects that are formally mounted or fully connected as parts of the final assembly. Here are a few suggestions:
Ensure a proper mechanical connection:
Try adding an appropriate connector footprint or mechanical mounting points rather than a single signal wire so that the module is recognized as an integral part of the assembly.
Review component properties:
Verify that the module’s properties indicate it should be included in the STEP export. Sometimes there’s a flag or setting for including external 3D assets.
Check export settings:
Look into the STEP export options to see if there’s a setting to include disconnected elements. Flux may automatically exclude items that aren’t fully integrated into the board design electrically and mechanically.
Following these steps should help integrate your module into the STEP export.