Bottled aforementioned beer today. Appx 3 weeks primary. The bugs and yeast formed a bizarre gooey sludge at the bottom of the carboy. By themselves, they didn't do this in the respective starters. It seems like some biofilm.
SG 1.030. FG 1.004. 86.6% apparent attenuation. Crisp and tart, but not quite as tart as I had hoped.
Bottled half as is. In the other half, pitched a little slurry of wlp644 brett to see the outcome. Hopefully no exploders in the coming months.
In the future, I'm going to do a 100% lacto ferment then pitch the brett at bottling to see the outcome. The wyeast lacto seems perfectly capable to do this.