Yes I completely agree if your bunny has had this problem since Thursday then it is an emergency, I feel that you should not wait to take him to the vets, as they can give drugs to stimulate his guts.
Trying to give Charlie food yourself is all very well, but it is the fluids he really needs, and the Vet can give this under the skin to rehydrate him.
Time is of the essence with these things, and we take bunnies straight to the vets within a day or so of their not eating, so that the drugs to stimulate the guts can be given.
It should not cost too much money for these drugs, and fluid under the skin though, then you can try feeding the bunny at home.
Charlie wont eat if his guts have slowed down or stopped , he needs drugs to get the gut working, and fluids to help push things through.
Has he passed any droppings at all, if so, when? what did they look like?
Is he drinking?
best wishes and good luck
Getting water / diluted pineapple juice into him is your priority, I would not worry about food just yet, fluids are the most important thing at this stage. He may get stressed with you syringeing too many things, just see how he takes the water first.
I would give him 3mls of water every hour till bedtime, and then perhaps once throughout the night...and then from earlymorning every hour till you get him to the vets.
Be careful that he does swallow the fluid as you slowly give him some by syringe, as if he does not take it properly it can go into his lungs..place a finger under his throat and you will feel him swallowing it. If he refuses to swallow the fluid, then it really is an emergency and you need to get to the vet asap. A rabbit can die within 12 hours from dehydration