If Neymar can play a full season for Al Hilal then I believe Al Hilal management will be very happy with his performance and will be interested in extending his contract.
Now the only prayer for Neymar is that he stays injury free and plays the full season fit for Al Hilal and Brazil
From what I can see, the Saudis have so much money, so much money that continuing to pay an injured player will never be a problem. As I said before, the marketing return that Neymar brings makes up for the lack of games... His contract ends next year, and by Neymar's choice he will return to Brazil to play for Flamengo, I'm almost certain of that. It won't be for lack of renewal offers, but rather by the player's choice.
Buying a player, the player is fit for the whole season but he doesn't perform well, so the club can rely on him for the next season, but if he is injured every season, there is no chance to rely on him.
Neymar is a racehorse but he is sick and sick horses are underrated. Neymar will have to play the full season next season with utmost caution, only then will he be able to play at Al Hilal until the 2026 World Cup.
I believe that if he returns, it will take a few more months to acquire the ideal conditioning and playing rhythm. The injury he had was very serious and even the player himself was discouraged by the slow recovery. Maybe he will play out the last year of his contract but he probably won't want to renew it. He has plans to return to Brazil... His destination will probably be Flamengo.