I doubt that both the electric auxiliary heater and the coolant pump failed simultaneously yet both were replaced. The official BMW electric auxiliary heater replacement procedure doesn't include replacing the pump and vice-versa. So unless there's a valid explanation, replacing both seems excessive.
$42 is the retail price for 1 liter of i3 coolant concentrate. A 50-50 mixture with water protects against freezing down to -40º. You were charged for 2 liters of concentrate which would have made 4 liters of coolant, double the capacity of the coolant circuit. Maybe additional coolant is needed for the filling process. Or maybe not…
You were charged for 1 hour of labor for a vehicle inspection. If you asked for a vehicle inspection, that's fine.
You were charged for 1 hour of labor to update IHKA software. I'm pretty sure that the IHKA software can't be updated without updating all of the system software (i.e., by increasing the integration level). If the integration level was increased, 1 hour of labor is a fair charge. However, there's no need to update the IHKA software when the electric auxiliary heater is replaced unless a new version incompatible with the existing software was installed. This seems very unlikely. Maybe the description is incorrect and "update IHKA software" is really "register the new heater with the IHKA controller". If so, I doubt that this would take anywhere near 1 hour. Maybe 1 hour is their minimum labor charge.
I hate to see anyone overcharged for i3 repairs. It feels like you were charged liberally for this heater replacement. However, I might be wrong never having had the heater replaced in any of our i3's.