The Cardinals are not actively trying to trade to Bader, no. They still believe in his upside, and they don't want to trade at this point, not when they think they can get more from him as a player and won't get that return for him because teams would be looking to grab him for his upside. Arozarena is not on the 40-man roster. That matters. It matters for multiple reasons at this time of year:
-- The Cardinals have a lot of outfielders on the 40-man roster, and if Arozarena is coming up as a place-holder and not a starter, there's an option year that they burn without having to burn it. So, if Fowler is the starter in CF and Bader is the backup, then is Arozarena going to leapfrog Fowler? Is he going to leapfrog Martinez and move Fowler back to RF? If there was a time to move him up, it was when Ozuna was injured, not when Ozuna is on his way back.
-- Any teams interested in Arozarena for a trade, are going to, in part, like the fact that he's not on the 40-man roster and that he's not down an option or about to be down an option year. That increases the flexibility he offers in any trade.