@lolokxd maybe set up trick room, kill couple of mons with a-marowak or use gardevoir in trick room, if I remember correctly samson has some pretty fast mons on his team (hawlucha and mienshao come to mind), when either marowak (or gardevoir) is taken out or trick room ends, bring out some mon to sack and use that time to heal up gardevoir to full health, then proceed to kill a couple mons with that, in order to take out that annoying hawlucha I'd suggest catching a crustle with sturdy and killing it off with a rock wrecker
I think you can also catch a braviary or hawlucha on route 2
Sadly I dont really remember the mons that samson has so I cant be more of assistance but maybe these help enough or someone who has a better memory sees the post and is able to help out more
But definitely lvl up your mons closer to lvl cap