I still believe there is no Bizarro Superman in the film. I believe Doomsday evolves from Zod especially given Shannon's comments about flipper hands so I'd say he's going the mo cap for it. So unless Lex somehow gets Superman's DNA I see no proof of Bizarro.
In MoS, when Superman is aboard the Black Zero in a weakened state due to the Kryptonian atmosphere, Zod's science officer takes a blood sample from him. That's how they determine that the Codex in hidden within his cells. Presumably Krypton's super advanced computer AI shares data between ships. So its plausible to me that when Zod comandeers Superman's scout ship at the end of MoS, there may have been some sort of retrievable data exchange between the scout ship and the Black Zero.
So the DNA data for Superman would presumably be stored in the AI database of the scout ship.
It is mind-boggling to me that the scout ship, best we can see from the most recent trailer, ends up in Lex's hands. We can see that Lex gets Zod's corpse from the military, so I think it is a fair assumption that he has access to the scout ship from the military, as he is contracted to reverse-engineer it for them. This means that the Superman has left the ship in the hands of the military. That will prove to be a monumental error in judgment--or at least to have horrifically negative consequences (Lex creating Doomsday), whatever Superman's intentions in doing so. I think that Superman allowing the military to have the scout ship will actually alarm Batman (for good reason), based on his own espionage of A.R.G.U.S.
Interestingly, in the
Man of Steel Prequel comic we see that Kryptonian scout ships, by virtue of
their advanced bio-tech, apparently have the ability to self-repair or self-heal themselves.
The ship shown in the prequel comic panels above is, by the way, the very ship that is featured in in MoS. If this comic is canon for the DCEU films, the scout ship has therefore
already repaired itself once from catastrophic damage.
So my assumption prior to this trailer was that Superman would have taken the self-repaired scout ship and made it into his Fortress of Solitude. I think perhaps we will yet see him do that by the end of BvS. But anyway, it's just crazy to me that Supes allows the military to get their hands on the scout ship, as seems to be the case from the most recent trailer.
Anyway, to sum, in this scenario Lex would have access to the scout ship with its birthing chamber, Superman's DNA, and possibly some or all of Bertron's DNA code for Doomsday. And as we see he has Zod's corpse as well.
If there is a cloned Superman (
in addition to a version of Doomsday created from Zod's stem cells) the question becomes how does it advance in age so rapidly to become a full grown Superman of the same age? I'm going to guess that Bertron's DNA code for Doomsday has the creature grow and adapt at an astonishing rate. So maybe there is an acceleration of such a rapid growth strand from Doomsday that Lex splices into the Superman clone...
All speculation, obviously. But personally I love the detective work of trying to identify and piece together various clues such as this in order to guess what the story might feature!