https://www.youtube.com/watch?v=V2f-MZ2HRHQ
911 calls do tend to hype the responding officers into overreacting.
What is interesting about this 911 call is that the caller appeared to present a considered assessment: suspect "probably a juvenile" and "gun probably a fake", both of which proved to be true.
These officers will not be able to blame the 911 caller, not that that is ever an excuse.
It is entirely possible there was more than one 911 call, with divergent reports as to what was happening.