I surf at Ala Moana occasionally and sometimes pay attention to the non-native flora there. The tree with the red flowers and big thorns sounds like an Indian Coral Tree AKA Indian tiger claw. They are used a lot in landscaping, are not native, and are in the Fabaceae family. Erythrina is the genus. The other tree I'm not sure of. Where in the park did you collect the seeds (Diamondhead end of the park or Ewa end)? I'll have to pay more attention the next time I surf there.