I believe I was able to duplicate this...
I installed HubLink on one Hub and Link to Hub on the hub with a ZWave RGBW bulb. I know it's not the Hue, but then I don't own anything from them. This is as close as I can get. 
I added the RGBW in Link to Hub and the virtual device was created on the hub running HubLink.
I can turn the bulb on and off from the HubLink hub, but I cannot do a "setColor". Logs show the command occurs and is received by the Link to Hub hub:
dev:582 2019-07-27 10:36:47.278 pm debug setColor([saturation:100)...
dev:1576 2019-07-27 10:36:47.241 pm debug parse color,[saturation:100, hue:35, level:100]
2nd attempt:
dev:582 2019-07-27 10:40:09.516 pm debug setColor([saturation:89)...
dev:1576 2019-07-27 10:40:09.482 pm debug parse color,[saturation:89, hue:35, level:89]
However, using the setHue command, does work.
dev:582 2019-07-27 10:41:17.111 pm info Hank RGBW LED Bulb colorName is Medium Spring Green
dev:582 2019-07-27 10:41:17.104 pm info Hank RGBW LED Bulb RGB is [0, 255, 163]
dev:582 2019-07-27 10:41:17.101 pm info Hank RGBW LED Bulb color is #00ffa3
dev:582 2019-07-27 10:41:17.098 pm info Hank RGBW LED Bulb saturation is 100
dev:582 2019-07-27 10:41:17.095 pm info Hank RGBW LED Bulb hue is 44
dev:582 2019-07-27 10:41:17.089 pm debug setHue(44)...
dev:1576 2019-07-27 10:41:17.050 pm info vr_Hank RGBW LED Bulb colorMode is RGB
dev:1576 2019-07-27 10:41:17.046 pm info vr_Hank RGBW LED Bulb colorName is Black
dev:1576 2019-07-27 10:41:16.985 pm info vr_Hank RGBW LED Bulb hue was set to 44%
dev:1576 2019-07-27 10:41:16.721 pm debug parse hue,44
On the other hand, HubConnect works just fine, no surprise there....
dev:752 2019-07-27 10:43:34.411 pm info UpperBath Sink Dimmer is at 22% [digital]
dev:752 2019-07-27 10:43:34.410 pm info UpperBath Sink Dimmer is on [digital]
dev:582 2019-07-27 10:43:31.315 pm info Hank RGBW LED Bulb colorName is Dark Violet
dev:582 2019-07-27 10:43:31.309 pm info Hank RGBW LED Bulb RGB is [189, 0, 255]
dev:582 2019-07-27 10:43:31.307 pm info Hank RGBW LED Bulb color is #bd00ff
dev:582 2019-07-27 10:43:31.299 pm info Hank RGBW LED Bulb saturation is 100
dev:582 2019-07-27 10:43:31.296 pm info Hank RGBW LED Bulb hue is 79
dev:582 2019-07-27 10:43:31.293 pm debug setColor([saturation:100, level:100, hue:79])...
app:837 2019-07-27 10:43:31.278 pm info Received command from server: ["Hank RGBW LED Bulb": setColor]
