I don't know much about plumeria, but the bumps look like roots to me.

Extrafloral nectaries?

If you scroll to the bottom of this post, it talks about those, so could be!

https://www.houzz.com/discussions/2123377/clear-sticky-substance-on-my-plumeria

https://duckduckgo.com/?q=plumeria+ariel+roots&t=ffcm&iax=images&ia=images

did you take the cutting just below a node???

how about a pic of the whole cutting .. is it potted .. does it have roots ... etc...

ken

I planted the cutting about 5 weeks ago. After 4 weeks I checked for root growth and had none. I then reported in a cut water bottle (saw online) so I could easily see If roots are growing. I’m wondering if that contributed to some of the black on the leaves.

In my experience, the yellow dots aren't anything to worry about and some cultivars have more than others...but black on the new leaves could be an issue. The cutting looks robust, so keep at it and give it some bottom heat if you can.

-s