If you have a fighter with high Int and Cha, then you should not have any problems with dialogues, even if you can't max the skills (because they're cross-class). Int gives you the skillpoints needed, Cha the bonus. You can select an appropriate background feat, bonus again. You have access to many feats thanks to being a fighter. Use the fighter bonus feats for fighter specific stuff, so you'll have feats left to spend in dialogue specific feats, especially if your character is human which grants you an additional feat, bonus again *. Then there is equipment increasing your dialogue skills (--> hats), more bonus! If companions don't go on telling you something it's not the dialogue skills that aren't high enough, but rather your influence on them that needs to be increased.
For comparison: My ranger/druid didn't have class access to said skills yet thanks to background feat and his marvellous hat he mastered every dialogue sequence.
I don't know the console commands either.
*: Unless you're a powergamer and want to max your fighter, then there's nothing left for dialogue pushing...