and it dates back to January 05, 2012
I searched both of those and found no use of the word "halvening". Are your links correct?
Actually you were not supposed to search for halvening since I stated "halving" but not "halvening" in relation to those links in my post. They represented my initial intention to dwell on one part of the origin of the word "halvening".
In opposite to other suggestions of "halvening" origin, i.e. Doge coin community discussions that encouraged some Reddit members to use it more and more often, I stick to the point that creation of "halvening" term was inspired by combination of "halving" and "hapenning".
I suppose that roycilik post in this thread quoting "August 11, 2012, 09:03:42 PM" as the first time use of "halvening" confirms that it was neither Doge coin community to create the term "halvening" nor Reddit community to take it from them because Doge coin was introduced after that date.
During further research I found some more links supporting the points regarding origin opposite to mine. They claim that it is just stylization of "halving" https://cryptocurrencyfacts.com/bitcoin-halving-explained/ or http://bitcoinandmarkets.com/glossary/ (when adding ending "ening" like “The Flippening.”).