Thanks for sharing! Maybe one of the EF developers can comment on this behavior?
Just to emphasize for all the readers: working directly in the AF SQL database is highly discouraged, and should only be done in case there are no other viable options. Use the AF SDK or one of the tools provided if possible.
I suggest you upgrade to at AF 2.4 (PI AF 2010 R3) as that is the first version of AF that officially support PI Event Frames. If you are using EF with AF 2.3, you're doing so as a CTP and I recommend that you do not deploy that configuration in a production environment. There are known deficiencies.
As a side note, thank you for opening a tech support case on this. It helps us very much.