Those green 'titanotas' are all misnamed and should be named Agave oteroi or oteroi hybrid. From the start of the appearance of the green 'titanotas' on the market it has been pointed out that those do not fit the original description of Agave titanota at all, but they are really cool plants so people snapped them up and more and more were sold to the point that when they finally 'officially' sorted out what those plants should be (Agave oteroi), the name Agave titanota had become so ingrained that it will likely stick around forever, but it never was the correct name for those plants and since a few years ago it is officially not the correct name.
Any 'titanota' that is green or with a clear midstripe is Agave oteroi or an Agave oteroi/titanota hybrid, possibly with some Agave kerchovei mixed in since those all occur very close together in certain areas. True Agave titanota does not have a midstripe nor is it ever green. The name 'titanota' actually is in reference to its alabaster color. Already implying that the deep green plants had to be something else, it just took a while for that to be sorted out officially.
Check out the picture of Agave oteroi in my post above and you will see that the plant in your photo looks a lot more like that.
