Rather than admit some internal planning error on the part of their summer program, the flustered manager chose to blame you. When pressed to identify some personal failure or an 'elephant in the room', some Chinese managers may lash out, unaccustomed to direct communication or apology.

Mere supposition by you; internal planning error, my arse.

You are like a 'homer'. He is a soccer referee whose decisions tend to favor the home team during a match. When the crowd picks up on this, he will be jeered and booed whenever he has to officiate during the rest of the match, and quite rightly so!