Well, yeah, easily disputed and it's hard to diagnose a broken heart.. I got that story from David Gage who has a bass repair shop in NYC and was a friend of Mingus'. As Gage told the story to me after I tried for years to get hired in his shop, Mingus was angry at the way things went down before Dolphy collapsed, where the disputed stories of his death pertain to events after the collapse. Assuming Gage was truthful, maybe Mingus embellished in anger and his own heartbreak over the loss of a dear friend in such a petty health mistake. Supposedly Mingus claimed that Dolphy was heartbroken at having to leave America to find adequate audiences for his American music, and stopped taking care of himself in ways that Mingus viewed as somewhere between grave indifference and suicidal. According to Gage, Mingus smashed his bass in anger at the death, and Gage glued it back together for him. As far as Mingus accusing a nation of some notion that American indifference to Dolphy had caused his friends death, that would likely have been hurtful to his position and income, accusing and pushing away an arguably dwindling fan base for a music that took devotion of fans to support. Maybe there was also some feeling of guilt in Mingus for not saving his friend from himself. There are stories of Mingus making Dolphy play his bass clarinet behind the curtain, because audiences might not be receptive to such a funny looking fiddle in a very traditional vehicle. As far as Gage being a reliable source, I found him to be largely unfriendly, while I was mostly a PITA as a customer who spent little money but much time, and kept asking questions. I think it was several years before he told me any stories, and I recall when I was looking for either a heavier cello bow or a lighter French bass bow for playing electric cello, I saw a bass bow hanging up and took it down to ask about it. This pissed him off and he grabbed it away from me, saying Mingus had given it to him. That might be when he told me that story, FWIW.