I've had these for about a year and they haven't flowered and I have no idea what Adenium/s they could be. Does anyone know? The smaller one had a really rough start.

It is hard to tell from the photo but most adeniums are obesum. If it has fuzzy/velvety leaves then it could be an arabicum hybrid.

There is a black dot on the smaller one, is that from the sap or a rot?

It might need more light to flower. As I previously mentioned Ylis and Nancy have used grow lights on their indoor grown plumerias and they successfully bloomed.