The trope, formerly named "Solicitation Mistaken For Help", is about someone's Double Entendre being misinterpreted as literal by another character, yet the title betrays the trope's definition.
I suggest renaming it to "Innuendo Backfire", in the style of Insult Backfire.
Well, not all the examples are subtle enough to be innuendo, but I think it's a good suggestion.
How so? An innuendo is made, and it backfires - the trope name looks descriptive to me.
By way of Missing Supertrope.
Show a teaser portraying the normally upright hero acting in an evil and despicable manner, causing the audience to wonder "Shock! How could this be‽" and then, hopefully, to read/watch/listen to the thing you're advertising.
You look at the cover to the newest issue of your favorite comic, and what do you see? The Superhero, apparently killing his Sidekick and his love interest! Or, "On the Next..." episode of the new prime-time TV series, the main character goes bad, selling her team out to the Big Bad and shooting the Plucky Comic Relief in the face!
— - hypothetical description of Paratext
I think that's something different from what we're discussing here. (And it isn't paratext, either.) You're describing Bait and Switch there, but that isn't what innuendo is.