It’s actually an H. Carpintis, my latest test. Both these oscars are old, and have had multiple tank mates over the years. Some they are ok with, others they are not. I’ve found that all I can do is add the fish when they are small and see what happens. I’ve had to scoop battered fish out before, and I’ve also had to separate more aggressive fish out as well. I’ve also fed them expensive snacks if you get my meaning.
The fact that yours allows tetra’s is great. I’d definitely leave them.
And sometimes cichlids can be stressed from being in the same tank as a large predator. This can lead to diseases, starvation, or simply getting beaten to death. Or, it could work. It’s a gamble my friend. I’m personally surprised those goldfish aren’t snacks either.