The other line items are probably similarly unrealistic since they include their own launch costs as well.

They also spec 300 racks of 500kg each, which is <40% of the weight of the comparable land rack. I doubt the full weight reduction since the racks still need to survive launch force/vibration in addition to fluid/pressure enclosures that land racks don't require. I think it's likely that just about every part of this report has a similarly cooked numbers, and we can just throw the whole thing out.