You might try killing a few of the people on the "Dark Side Hit List" to gain even more influence with Mandalore.
I can't remember all of them but I know that you can kill...
Lootra (Nar Shaddar)
Lassavaro (Nar Shaddar)
Guy in the Apartments (Telos)
There are some more but those are the only ones I can remember for now. Try to only have only Mandalore with you. If you have HK, Visis, Atton or Hanarr they might get the influence rather than Mandy...teehee, Mandy!
I know influence is quite finnikie, I'm pretty sure it's impossible to get full influence with everyone, so you kind of have to dicide who you really want to have influence over close to the start of the game.
I've yet to get Bao-Dur to turn Jedi cause there just aint' enough influence to go around.
Cheers to you all.