Many people do various things. I can't really speak to this particular event.
Prana Pratista is the correct way to energize the image, with or without Mantra Pratista however.
In my mind, it would depend on how he views and explains his activities. If the carving was of an authorized murti, then it sounds proper to me.
To my mind, there are a few things that determine whether or not an image is an idol or a murti. Part of it depends on whether or not the image is authorized in the scriptures and undergoes the proper rites. Another consideration is the attitude of the worshipper.
Murtis can be made of stone and the person who performs the installation can certainly worship the murti. The rituals of installation are defined in the scriptures.
I'm not really clear on what you asking here. It sounds like a standard installation rite to me. Perhaps you are thinking this rite is pointless idol worship? If so, you should study to understand the difference between an idol and a murti.
Om Santi,
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