Combeferre checks what the tome in the Library referred to as the anbaric spectrometer, connected to the strap around Bahorel's arm. He'd had to ask Bar for this machine, and specify materials very carefully. The manganese-titanium alloy it had called for had made Combeferre nervous; it had prompted Bar to give him a warning note with his supplies.

So Combeferre is sticking to the most conservative experiment, the one which poses no risk to Bahorel's daemon (assuming she is indeed still there).

...and the spectrometer is saying yes. More accurately, it's shouting yes.

Combeferre is grinning.

He makes a few notes on his tablet, turns off the machine, and unstraps Bahorel. "Yes," he says. "She's here--there--inside you." He thumps Bahorel on the shoulder, still grinning.