Hi
Young emerging leaves might not look exactly like older ones by Rhodiola rosea. But if by notched you mean with small indentation on the tip of each leaf, you can see a first one appearing on the most behind leaf on the top of the plant. The feature should become more obvious on the following leaves, and I think I remember leaves on Rhodiola don't look exactly the same on each plant. Might be a bit variable thing.
I thought of Sedum anacampseros as well, but I don't believe it has such a thick leaf appearance even at young stage, and should really show well rounded leaves everywhere, without any trace of indentation.
So I would also stay on Rhodiola for the moment.