Disney sent in both Alans to go through the whole 20th slate. To think they sat around the table and just had straight thumbs-up / thumbs-down votes and didn't delve-into these projects with their staffs and call for changes where needed I think is very far fetched personally. Alas, going in and cutting approved projects (perhaps even cutting the continuation of David's story) or re-organizing projects for streaming, can already qualify as the "Disney meddling" fans had fear about.
In regards to someone being fired and the decision coming from above a Kathleen Kennedy or Kevin Feige i.e. Disney, often that logically won't come out, unless Disney feels they have to make a statement, and someone's furious as much as confident in their position, like Kevin was when Alan Horn had James Gunn fired. A less scandalous situation and a lesser track record / less clout chief working underneath, it will always be a vague firing to us "over creative differences". Airing all your fights with Disney pubically in the press would be career suicide I think in more often then not. Gotta take the heat yourself in most cases and tow the company line.