It was already clear that Rashford would go to Barcelona, the whole issue is in registration and now, as I understand it, there is no progress there. The deal for Pau will definitely not be very significant, the entire transfer costs 15 million - as much as Rashford's salary. As I understand it, they need to follow the 1:1 rule regarding salaries, so in order to register Rashford, they need to release players who collectively earn as much as he will earn. In general, Barcelona faces a difficult puzzle.
Ter Stegen + Pau Victor being sold could have fixed it.
Although, i heard Ter Stegen's will be undergoing another surgery but still doesn't change much for now.
Again, I read that if an injury spans beyond four months, it could create room for a signing like Marcus Rashford, especially with Pau Victor also on the line... But Ter Stegen himself mentioned a three month recovery. This could be a twist though as there're no official announcement from Barcelona yet, but they might declare a longer period to qualify it as a long-term injury IMHO
Pau has a tiny salary compared to Rashford, Barcelona can sell 10 of these players and it will still not be enough to make room for Rashford's salary. As for Ter Stegen, he does not want to leave Barcelona because he believes that he is capable of being the number one goalkeeper in the club. Even though the club chose the other two for the short term + long term, so selling him will have the same problems as with De Jong, he just does not want to leave.