generally speaking, myocarditis itself will not cause ongoing inflammation in this fashion for an extended period of time. Usually this lasts for ~4 weeks to 3 months pending the etiology. Now, if he had COVID, dropped his EF and had heart failure with reduced ejection fraction, then yes absolutely he would be at increased risk of ventricular arrhythmias (which would be a proposed mechanism for his collapse--> ventricular tachycardia). The way I'm reading the commentary, which is from a news story and not from his doctor, is that he has acute myocarditis, which would be odd to see this far out in terms of causing ACUTE myocarditis which is where my commentary on this came from.
I haven't seen COVID lead to 6 months of ongoing myocarditis. I have seen it tank an EF and put someone into heart failure and predispose them to arrhythmia. Perhaps semantics, but I think an important point in how they're running the story saying that he has myocarditis that has been linked with COVID, but not stating that the doctors have said this case is caused by COVID. Only point really I was wanting to make is that this would, if they documented that it was from COVID, be a major impetus to push towards cancellation.