Hello I will help you with your question,
The fitting works by squeezing the white tabs and then you can pull the hose out of the fitting. The hose end is sealed with a O ring.
If the fitting in the manifold is not leaking I suggest that you attempt to replace it before it does, if you can get it out you can install a threaded hose end so the hose is installed with a clamp.
What usually happens is the galvanic action erodes the hose end fitting to the point the O ring no longer seals and this same galvanic action erodes the metal of the fitting in the manifold.
If the fitting in the manifold cannot be removed cleanly and the threads chased with a pipe tap the manifold would have to be replaced.
This is a 50/50 chance the fitting breaks in the manifold unless it is leaking and then it is a 90% chance.
Let me know how I can help you with this