Upon installing the gimbal and initializing the launch process everything as far as having no errors and good video, with recording to media card, is working.
Perhaps some video parameter adjustments could be effected inoperable but as it is in 30fps and 4k and basically automatic, all is OK.
It is not unusual for some transmission lines to be spare or have a use only on the bench, I guess.
Still hoping someOne finds a reseller of this cable…….