At the moment Danny Olmo is still not registered and will not take part in Barcelona's first game against Valencia and I think that if Barcelona could have registered him, they would have done it already, because it is unlikely that Barcelona would have paid 60 million euros for him.
Although Flick says that Olmo is not fit yet, but I think it is just a formal excuse, because Olmo played his last match more than a month ago in the final of the European Championship and it is unlikely that he has not had time to recover yet.
To be honest, in the past week I have not followed the development of La Liga, as well as the situation of Dani Olmo. It's just that a situation like this reminds us of when Xavi also had difficulty registering some of his new arrivals, but they registered them in the end. I'm sure at least Barcelona has prepared in advance, even though Flick as Barca's coach made a statement saying that Olmo is not fit. It could be, it's just to reduce the commotion. Barcelona will start their match tomorrow away to Valencia's headquarters, if Olmo is not registered, it means he cannot be played. Maybe that's why Hansi Flick was appointed to say that Olmo is not fit. It's just a matter of time, maybe the day after tomorrow Barca will solve it. If not, why would they bring in Olmo if he can't be registered.