So that's it, Skye didn't come in the house during the night and we weren't able to lure her in. We took turn at getting her to stop barking throughout the night, until 4am when Peter offered to stay with her outside for the remaining of the night. Here they were after I got 2 hours sleep:
He is now in bed while I a writing this.
We somehow ruined the house for Skye, and the more we think about it (got a lot of time to do that overnight!) the more obvious it becomes. All the fun things (training, enrichment game, play, chasing critters...) are happening outside and all the stressful ones are happening inside (visitors, greeting them in the kitchen, computer/phone beeps, being "trapped" inside at night when seeing critters outside or hearing cats yowling....). Also there is the threshold of coming in the house which even with the door completely opened is a stressor for Skye. So why would she ever want to be inside? Especially since the weather is very nice here in California.
I think we need to rethink a few things, make all good things happen inside, and maybe make it less comfortable in the yard (at least at night).
To be continued...