It wouldn't be because of the soil conditions - maybe it's due to a difference in light exposure between the two planting sites. Otherwise, were the new ones in flower when installed? They look to be younger and smaller than the older one.

They are younger, planted in August but potted versions of even smaller cossandra plants at local nurseries are full of flowers. The larger plant is in my entry walkway and I would say gets less sunlight than the others. I was gonna look into soil conditions but all reviews I read say its a easy to maintain plant in South Florida due to the heat and humidity, and the leaves are very green. Maybe the palm trees the border are robbing all the moisture? IDK. Would lover for these to start flowering.

Your problem is that there is no soil around palm trees for them to get their nutrients from. Palm roots take up every spare bit of space and suck the nutrients right out of the soil. Just move them to a place where they can have at least 8-12 inches deep of soil and they'll do fine.

This is why people put bromeliads around palm trees. I'd get some nice neoregelias to put around those palms, or put the crossandras in containers around them.

Except the tops of the crossandras have been growing and look more or less normal. Lack of adequate rooting space would interfere with flowering by interfering with development of the entire plant.

Root spacing and the "demanding palms" could be my issue. I think I'll combine both your advice and transplant the crossandras to the back yard and plant a more "palm" friendly plant in its place.