Here is the full list of all 15 Cash Cow DX achievements.
Win easy mode
Go down 50 slides
Beat speedrun under 5 minutes
Clear all enemies in stage
Tripple diamond combo
Beat stage on 1 life
Eat a watermelon
Complete EXTRA
Score 1 million moooney
Offer enemy a lift
Set new high score
Practice makes perfect
Zero cows wasted full run
Beat hard mode
Gatecrash the party