Ok, there's a trick here now that I'm only just catching - ESPN is using a Gb/FB rate that includes line drives as air outs, while MLB.com is not including line drives as air outs.
HOWEVER, MILB.com is unclear on which it is using. If MILB is successfully breaking out line drives for A ball players, then you're right, and Madrigal's #s are poor but not the worst in the league. I didn't catch this beforehand. BUT - if MILB.com's statistics are lumping together anything hit in the air, including line drives, as air outs, then the # being reported by MILB.com would compare correctly to the big league number reported by ESPN, not to the number reported by MLB.com that has subtracted out line drives.
If I had to guess - a traditional score table from an A ball game will show ground balls versus anything in the air, but will not break out line drives. I could darn well be wrong on this, but I did not catch this previously and MILB.com doesn't say whether their air outs # has included line drives or not.