The point is, you shouldn't borg anyway if you're not willing to lose the humanity. Thats part of the cost of borging.
Also, it does state on the cyberware page
Quote:All cyberware implants have a maximum rating, and cannot be traded or sold. Humanity lost can never be recovered, and currently the chop shop does not perform removals or upgrades to a other cyberware tech. So select your cyberware with care, as it cannot be removed... only purchased again to improve its rating.
That paragraph tells you right there you are losing your humanity from the borgs and it can never be recovered. There should be no way to recover from something like that, including fucking buying it.