You need to progress with the lab assistant quest first. At some point she will say something about bringing your slaves to the lab. I also recommend you upgrading the tank capacity a few times as well.View attachment 4980975
Anyone know how to milk a slave at the lab? People say you can do it but Eliza is never here when I leash a slave
The slaves in my save were already trained. I don't know how much you will need to train one to be able to take to lab.