First sign of trouble to me was "younger brother-in-law" instead of "younger stepbrother". Same word is used for both, so the translation depends on the context.
Skill sure suffers from a massive downside in regards to time from preparation to execution. Here they were thankfully able to withdraw to some cover, but he's at a disadvantage for any situation that would require him to "whip it out" instantly.
While the attack happened at night, all of the interaction with the First Empress is during the day. First Rudolf says "Last night, a rat seems to have slipped into this palace." And pages 15-17 of 10.1, as well as 5-7 of 10.2 make a show of sunlight both inside and out.
Ed must be a reincarnate from Japan, who knows from reading countless stories "Boy, things sure would be better if these characters just talked to each other properly. I wish I could somehow tell them that..."