Upekkha and Non-attachment in Buddhism
I don't understand the whole quoted text, because my english is terrible, however I understand upekkhā-brahmvihāra's enemy, so I will explain just it:

Near enemy = fake-upekkhā = unwholesome mind that acting like upekkhā, but it is just a lazy and a fool mind that don't has any knowledge to manage that situation, so fake upekkhā just acting like upekkhā, but the real mind is difference.

Far enemy = appeared enemy = antonym of upekkhā. upekkhā mind factor is in the middle way between unwholesome mind especially lobha and dosa. So lobha and dosa are an opposite of upekkhā.

I am not sure that you already knew this:

In path of purification, visuddhimagga, said that there were 10 difference phrases that upekkhā is used in tipitaka.

Your quoted text is upekkhā-brahmvihāra, tatramajjhattatā mind's factor. It is not upekkhā-vedanā mind's factor.