The following non-chaotic dwarves can be killed without losing access to Rolf: dwarf, female dwarf, small dwarf, dwarven elite guardian, drunk dwarf, grizzled dwarven veteran, dwarven gladiator.

This seems like an oversight, given the types of dwarves that cannot be killed without losing access to Rolf (e.g. muscular dwarf, dwarven guardian, dwarven weaponmaster).