Motivations for killing Rayna Boyanov in Spy (2015)?

Question

In Spy (2015), Sergio De Luca makes several attempts at the life of Rayna. Why does he want to do this?

Rayna is the only person who knows the location of the nuke. De Luca needs Rayna to deliver the bomb to Solsa Dudaev. Therefore, killing Rayna before this transaction doesn't make sense to me.

In fact, we learn later that De Luca needs Rayna to show Solsa and himself where the bomb is so that he can kill both, take Solsa's money and Rayna's bomb, and sell the latter to a higher bidder. A Rayna that is dead before the Solsa's meeting will ruin this plan.

Answer 1

Unless I'm seriously missing something, De Luca only tries to kill Rayna after discovering where the bomb is. We're never told that any of the previous attempts on her life were ordered by De Luca:

• The guy who poisoned her drink at the casino just says "F-You" and dies. He seems angry at her. His motives are never explained;
• The steward (Colin\Frederick!) who pulls a gun on her on the plane says 'some people really want what she's selling', so it's possible he wants to extract the location of the bomb from her, but this is never made clear. The pilot then says "Stan and I already sold it to..." but Frederick shoots him before we learn what he meant by that. De Luca's name, in any case, is never mentioned;
• The drive-by shooters turned out to be double agent Karen Walker (and another male CIA agent). It's possible that they were actually aiming for Susan in an attempt to cover their tracks (which is supported by the fact that Karen tries to shoot Susan once Susan catches up to them), but again, their motives for the shooting are pretty much left unexplained (and I can't imagine why they'd be working for De Luca anyway);
• Lia, who works for De Luca, approaches Rayna at the club to allegedly make a bid. Susan later tells De Luca that Lia's plan was actually to kidnap Rayna for herself. There's no indication that Lia was there to kill Rayna, though.

As this answer surmises, Rayna is a reckless, cruel woman who made many enemies; it's possible some are trying to kill her for unrelated reasons, while others are trying to extract the bomb's location from her. But I don't recall a single point in the movie where we're told De Luca ordered her death.