Help little Larry have a healthy life

We found Larry supposedly an 8 week old kitten on gumtree 5 days ago being given away by a family after having him for 2 days, they did not want to keep him due to their 

daughter being too rough with him and having
to keep him for his safety in their laundry all alone all day. We drove 1 1/2 hours from our place of residence to pick up and when we saw him based on his size we realised he was not 8 weeks old but due to the situation we thought it is best for him to be with someone who raised 
young kittens before. 

On the drive to our home we noticed that Larry kept crying and having diahhrea, we assumed that Larry was just stressed due to too much
change and when we bought him home we fed
him some Royal Canin Babycat food, he had a
hearty appetite and ate all of the food that was given, which was good to see. He then playedand decided to go to sleep because he is very sweet and affectionate so he preferred to sleep on our shoulders.

Twelve hours passed since 
his last meal and he refused to eat everything 
that was given except kitten milk. We decided to bring him in for a vet check up and we foundout that he is only 5 weeks old, anemic and is full of parasites. He was administered medicinefor the parasites which caused him to foam in the mouth and become very lethargic. He spentthe next 14 hours refusing to eat everything and only kept drinking water, he also had uncontrollable diahhrea that made him pass out in the litter box over night as he kept trying to use it, his bottom had to be washed as he stopped trying to clean himself. 

We decided to take him to SASH Animal hospital and we were quoted a $3,300 bill for 48 hours. We decided to pay for 24 hours and see how it goes but 12 hours later we received a call and got quoted $2000 will be due at 3pm which will be 16 hours after he got admitted to the hospital.

The vet surgeons at the hospital stated that Larry is refusing to eat, is having constant diahhrea, and has whip worms which are highly rare and complex parasites for cats to get. He has been put on IV Fluids via a catheter and they also administered some worming medicine for Larry but they would like to get some ultrasounds done to find out if he is not eating due to
having a knot in his stomach or worse.

We realised we can’t afford to keep him there as he would need to stay for another day for just a proper diagnosis and decided to call our local vet asking for some advice who told us that the vet nurses can attempt to save his life by taking care of him until he starts eating on his own. Currently he is being force fed by them as he is still refusing to eat, he is being lively and playful but he is still having diahhrea, we been told by the vet surgeons that he might be at 
most only 6 weeks old.

Our local vet has also made us aware that he 
only has 50% chance of survival with the vet 
nurses taking care of him.
We don’t want to give up on him and we believe he can be saved if he is bought back to the hospital, has further diagnosis and treated there until they find a cure to the diahhrea. Currently he is in a stable condition with the vet nurses but the prognosis for his chance of survival is very bleak and we want him to be brought back to the hospital. But it is very expensive and we can’t afford the medical care. Please, if anyone can help it would really mean so much for us and little Larry.