For Celta Vigo I really believe they will probably continue positive trend to not losing, I mean they will be consistent in the rest of this season so I also think they won't have much to do with relegation although theoretically it could happen. For Girona and Mallorca it seems these both teams will also stay in La Liga, but yes I agree that they are still unsafe because the current points are also not too far from Valencia, also their performance is not very consistent lately.
In the remaining 12 matches, everything is very likely to happen which team will eventually have to be relegated, and I see that starting from 13th ranking and below they are all not safe from the relegation zone because there are only very few points difference, unlike Celta who has more points of the teams that are struggling from that zone, but the saddest thing is to see how Valencia has been so bad this season and if they do go down this season then it's a setback and a change of coach doesn't seem to give the satisfactory results as expected until now.
Barcelona is seemed potential to get the La Liga title this year, when I calculate, Barcelona just needs 8 winning and 1 draw to lock the la Liga title. Even Madrid has won 12 remaining matches, but still, Barcelona will be got 25 points from those results. And, the final point could be 93 and Real Madrid gets 92 pts if they won all 12 matches left. But the question is, can Barcelona win 9 matches from 12 matches left? because some players are quite doubtful to play full on remaining matches because has potential of injury.
If they fail to win the league this season wouldn't that be a big failure for Barca? Failure will be even more painful because they have started well from the start of the season, especially being supported by their competitors who are not performing well this season, so even though they may experience difficulties due to facing several injured players, Xavi will maximize every available potential to still they can lift the trophy this season.