It called for scm. Creme of coconut is very sweet in itself so there was no need for added sugar. There is a very big difference between coconut milk and creme of coconut
I'm well aware of the differences between them. However, cream of coconut has a thinner viscosity among the differences making it not a great sub for some things like fudge.
You need to know the role SCM is playing in the recipe:
-it's either just a replacement for milk and sugar, making CoC a great sub
-or it's used for its thickening properties (among its sweetness and milky properties), making CoC a poor sub. SCM has milk proteins in it while all CoC doesn't. (Try making chocolate fudge with CoC and you'll get a thick ganache.)
CoC also has a coconut flavor, which you may or may not want. If you want one, great. If you just want sweetness without the flavor, the coconut flavor can be hard to mask (depending on the recipe).
Finally, all the above is in reference to Cream of Coconut. Coconut Cream is yet another different product. Coconut cream is unsweetened while CoC is sweetened. Unlike coconut milk which doesn't requite a hechsher unless it's a product of China, Coconut Cream and CoC both require a hechsher.
This article goes into detail about how each is made.