I've played on two Minecraft realms, and had the same problem when linking villagers up. They link to beds just fine, but for some reason don't link up to workstations, I've left a lecturn right next to a villager for an hour to an hour and a half and none of thr villagers linked. This has worked in my normal worlds so i know it works, but for some reason on the realms there seems to be a problem. I understand they may link to another villager, but it hasnt, I've checked all the villagers as well as checked that no green particles have happened over the lecturn