I wouldn't worry about Vinicius because he seems to be willing to be bought by clubs in the Saudi league.
https://talksport.com/football/3388563/real-madrid-transfer-news-saudi-pro-league-vinicius-jr/Of course 350 million for Vinicius is a lot, but if we remember what money the Saudi league spends on players every year, I think that finding 300 million for them is quite realistic and Vinicius will probably get 3-5 times more than in the real and this is probably the minimum.
I think if Saudis are ready to spend such money, then Vinicius and Real should agree, because with the kind of game Vinicius is showing now, he will soon have to sit on the bench, unless of course Alonso wants to lose matches.
This is a crazy sum, if any Arsenal player were to attract such amount to be sold they wouldn’t hesitate to send him over lol. I still believe Real Madrid can do without Vini Jnr even if they decide to sell him but it’s a really huge gamble, the club will need to have a deep thought on this before making any decision.