This may be a case of set vs. export. As a personal preference I like to put "export" variables into the dialstring itself so that I don't forget them. Also, it makes it a bit easier to know what is happening on the dialing leg. Try this:

Remove the set apps for call_timeout and ignore_early_media. (IIUC, enterprise originate automatically ignores early media, but feel free to set it anyway.)

Modify your data on the bridge app to be:
data="<call_timeout=10,ignore_early_media=true>FreeTDM/1/1:_:FreeTDM/1/2:_:FreeTDM/1/3:_:FreeTDM/1/4:_:FreeTDM/1/5:_:FreeTDM/1/6"

I'm just pulling this off the top of my head so don't forget about the standard disclaimer... Let us know how it goes.

-MC