Looks like Shinzon (well, at least his corpse) is in the trailer on a sort of operating table or maybe morgue around 1:45 of the trailer. Maybe the mystery girl is related to him? Would explain why a 1) she would have a connection to Picard (since Shinzon was a clone of him) and 2) a Romulan is saying "She is the end of all, she is a destroyer," since Shinzon was a Reman and they were considered a lesser class in Romulas and her father basically killed the Romulan Senate to get revenge.
Very excited for this!
Doesn't look like shinzon to me, looks like they're removing borg augments.