I am confused - there is no warranty coverage on your print head, so all options are at cost to you. You were offered a repair, which you accepted and paid for, and the print head worked for a while after you received it. What is your complaint? If I had been offered a 60.00 repair instead of a 159.00 replacement, I would have gone with the repair. And you state that support told you the head should not have been replaced, or repaired. I am confused, because you state both, and I have been offered the option on my failed print heads. I would think they would treat everyone about the same and offer both options if they are available. In your case, they offered a repair because it seems they were out of stock on replacement and that was the only option available. I am extrapolating what may have happened based on the information you present in this thread.
In my experience, having seen my share of failed print heads, that the o-ring failure that claimed your head can cause symptoms also caused by another failure and often can't be identified until the print head is tested either on a different printer, which is how I identify it, or by disassembling the print head. As I have never been instructed to disassemble the print head and have actually been told repeatedly not to disassemble the print head, how else was the tech to identify the failure? If yours was obvious, perhaps you should have brought it up before returning the printer? There was no sign of it on the original service for the print head, again extrapolating from what I know about CEL support. It seems to me that the tech was going with the most likely solution for the behavior you reported.

Technicians are human and make mistakes, but I don't see a mistake in this situation. The tech was working with the best knowledge available. I am basing this off what you have reported and what I know about CEL support from my personal interactions with them.

Are you referring to the other post on here about the technician "stealing" the printer? I read that post too and it seems like the user who posted it may be overreacting. If this user sent in their printer for repair, threatening a police report seems like a poor way to address the issue. Wasn't this user pretty abusive on the CEL forum to one of their techs several months ago? Maybe I have the wrong user, but the names seem similar, and I think I remember that user being admonished for personal attacks on the forum. If he is abusive on the CEL forum, perhaps he is abusive on his support tickets also and there is more to that story than was in his post?