childrens book: about two siblings, road trip, keep almost dying, parents never believe them

[Nadia]

I read this book in 5th-6th grade, its about two siblings, brother and sister, who are on this road trip with their parents and they keep almost dying- these two guys in bowler hats I think (?) keep trying to kill them but in really stupid ways like at a sound museum or something locking them in a room with the sound way up or trying to fry them in a museum about burgers and fries or something.
Random details I remember:
- the parents NEVER believe them
-the dad is obsessed with writing a book, and keeps stopping at the stupidest museums to try and get ideas (and keeps changing the book topic)
-the main villain was supposed to have died but then surprise survived
-the brother of the sibling pair remembers a bunch of obscure facts and has a photographic memory

[Rainbowheart]

What year did you read it?

[Kris]

A range of years is fine (e.g., 1980's, 1990's).

[Em]

https://www.goodreads.com/book/show/8...

Is this it?

[Rainbowheart]

Mission Unstoppable for Em's suggestion.