So, I'm trying to figure out the math. (Disclaimer: Yes, I'm a fool for doing so...)
Tsukiko is almost back to full HP after a Cure Critical wounds (4d8+15) and a Lay on Hands. The CCW could be expected to heal ~33 points. It's implied that Thanh isn't terribly high level, and doesn't seem excessively charismatic...say Cha 16 and 8th level, for 24 points.
The problem is that Haley's doing something like d8+6d6+Str+magic on each sneak attack (if she's 15th level, that's 8d6 SA), and Tsukiko eats three of those in the first round. Just from dice alone, that's 25-30 points/hit, so she's likely taking up to 90 points...which means there's quite a bit of damage unaccounted for.
I'd be a lot, lot happier if she'd said "Heal" instead of "Cure Critical Wounds".
Brad