If your PL 2 mooks have no chance of hitting Robin, you are not using enough maneuvers.
Get 10 Thugs at PL 2.
Have all of them perform Aim on one round. Next round, have 5 of them perform a Team Attack using Unarmed, while another 5 perform Aid for the Team Attack. Due to the +5 bonus from the earlier Aim, you are pretty sure to end up with a Team attack receiving +5 Attack and +5 Damage, for an effective PL 7 attack, which is pretty good for some mooks against a PL8 hero.
After Robin knocks out a few of them, they'll probably end up reduced to getting +2 bonuses from Aid and team Attack, for a PL 4 attack, which is considerably less threatening, but not completely inconsequential, especially if robin already took some Toughness penalties from the PL 7 attacks earlier.
Robin will still likely win, but can very well have to face the actual villain carrying a number of bruises from fighting all the mooks, and a stroke of bad luck could get Robin knocked out by the Minions.
Hell, get a single PL 4 Crime Lord with 20 Thugs. Half the thugs go for the Aid/Team Attack setup with the Crime Lord, while the other 10 provide Aid to his defense, and he can get to effective PL around 9 for a while, which can be a considerable problem even for a more reasonable PL 10 Batman, especially if the Crime Lord is not a Minion.
A similar setup can put a PL 8 to 10 Joker temporally higher than the the PL 12 Batman of the Justice League. Good thing he has Robin along and gas pellets to clean the mooks quickly, or he would be in severe trouble