Thank you. I should have guessed, but the leaves are so different than a "normal" hibiscus that they threw me off!

Thank you again, Tony. I believe C. batramia is what it is. It was one of the many rainforest trees the House with No Steps at Alstonville has. This one was amongst a bunch of red cedars and other types.

Acacia.

Some history- This plant started as a cutting from a Gentleman's personal collection. He brought it over as a cutting himself from a remote village in Mexico over 40 years ago. He has a large collection of these that he's been propagating for years. According to him (Mr Roger Martin,) it is a slow grower and only a handful of people in California have this plant. Those that do have it all originate from him. I asked him what it was but, he didn't know the name of it.