"Metabolism" is not a thing, it's a complex set of biological processes. So yes, people require varying amounts of calories, and feel satiated at different calorie counts, for all sorts of reasons.

In terms of your question (could two people consume the same amount of calories and end up at different weights if all other variables were controlled?), I have no idea how you would even go about testing this, but I think the answer would be no. You would essentially have to be testing the same exact person, just at different calorie intakes.

When I think about people with "fast" or "slow" metabolism, my first thought is about hypo- and hyperthyroidism. That's about it.