Zimmer was an extremely impatient coach; especially with kickers and OCs. His inability to handle the psychology of kickers was a huge issue on this team. He would openly doubt their ability/call them out for missing, then be shocked when they missed more kicks and looked to be without any confidence. Or, in Carlson's case, cut him after one really bad performance (and after wasting a draft pick on him) only to have him go on a be a fine/stable kicker for LV.
I can't access that article, but I wouldn't be shocked to learn a lot of the offensive problems the last few years were due to Zim, not the OC. If he's a defensive "guru," he should know better than to meddle in the offense. It doesn't matter how good your OC is if the HC won't give him some freedom to run the plays he wants.
I agree with you for the most part with the exception of Carlson. Carlson himself has stated that the reason he has seen success in LV is because he got cut from the Vikings. He took it as a kick in the ass and completely changed his kicking form, resulting in his success at a new location.
The whole situation could have been handled better yes but I doubt any coach was going to ride or die with a rookie kicker who was missing multiple kicks in a year where they had SB hopes.