Sounds like the old tool maintainer isn't leveraging their scarcity power. If their skills are in high demand and short supply, and they can't be replaced, then

Sounds like the old tool maintainer isn't leveraging their scarcity power. If their skills are in high demand and short supply, and they can't be replaced, then shouldn't they make things take longer as they learn new tool? Of course this accelerates the business’s desire to adopt the new tool sooner, so they best hurry!