Another observation. This "first encounter" is contradicted by Crump's recounting of DeeDee's phone conversation, too. Only one initiation of verbal contact in the DeeDee/Crump version of events, and that encounter is the one that ended with TM dead.
I think it's more likely that those second-hand reports of what was said by detectives is simply misunderstood, just like the "squeaky clean" misunderstanding.
And again, I question the whole narrative about Serino really trying to go after Zimmerman. Absent some other source than "anonymous" ones speaking to ABC News, I'm not convinced. Especially since the charging document presented as SOP could easily be spun by the media as "going after" Zimmerman.