Sophie had meningitis too. It is a long slow recovery but with lots of care they do get better. They need lots of fluids and antibiotics. It is good that you have got the vets on board early. Sustained high temperatures can cause a few circuits to get fried in their brains but the same happens to people and both dogs and people are able to 'rewire' with time. Hence, if he shows any 'odd' behavior once he is up and about don't be too alarmed. Be prepared for it to be anything up to 12 months to fully recover. With Sophie we knew she was out of convalescence when she got the old 'cocker strut' back into her walk.
I am sure that everyone's thoughts are with you and Alfie.
Rodney