
BeAuMaN |

Alright, rules for Radiant Charge (Bolded emphasis mine):
Prerequisites: Lay on hands class feature.
Benefit: When you hit with a charge attack, you can expend all of your remaining uses of lay on hands to deal extra damage equal to 1d6 per use of lay on hands expended + your Charisma bonus. This damage comes from holy power and is not subject to damage reduction, energy immunities, or energy resistances.
With a Lance on Horseback and/or a Critical Hit, I know you don't multiply the additional damage dice, but how about the additional Charisma Bonus Damage? And why not? I took a look at the "Multiplying Damage" rules in the combat section, and nothing really jumped out at me.

Kazaan |
The additional Charisma damage is "joined at the hip" to the damage dice from the ability. Say, for example, you have 3 uses of LoH remaining and +5 Cha bonus. The bonus damage dice for Radiant Charge will be (3d6+5) taken as a single unit. If your weapon damage is 1d8 and you get +10 from various damage bonuses, then your "whole" weapon damage dice is (1d8+10). In other words, the +Cha is a part of the {remaining_LoH}d6 damage dice.