It’s hard to imagine that a Drifter could be properly “captured”, so to say; from all we can find, it seems not-implausible that individual Drifters may operate as multiple instances of a base infomorph – imagine, say, a clone soldier being printed to many individual bodies at the same time, with all new info or knowledge gained by a given print being returned to the base data upon death to be included in future generations (somehow without wrecking their psyche).
If the Drifters are anything like this, I’d wager any such capture would be ultimately irrelevant, just as it should be only an inconvenience if a capsuleer were to be somehow “captured”, owing to the existence of infomorph backups (unless you happen to be the late Hilen Tukoss, whose final disappearance remains a source of great concern and vexation to me).