When a hooker attempts to steal a wallet from a drunken john, she accidentally makes a horrific discovery — the couple is not alone in a shabby room of a love hotel.

In my mind finding a dead body is a weak inciting incident because it is something she does herself, could have easily avoided and chooses to make something of it rather than just run away after seeing the body.

But if the inciting incident was her being accused of murder. That would be something that is done to her by an external force and she has to take action to fix it. More so presumably being a prostitute her character will be held at doubt and it would be harder for her to convince people of her innocence. So she has a built in obstacle as the MC.

When a down on her luck prostitute discovers an horribly mutilated body under the bed, she and her drunk john must evade the deranged owner of the deserted motel.

>>she discovers a corpse under the bed

That would be the inciting incident -- not the attempt to steal the wallet.

But then what happens? What problem does it create for the hooker (and john)? What must she (I presume the hooker is the main character) do about -- what becomes her objective goal? Who or what opposes her efforts? What's at stake for her? Is she going to be framed? Must she prove her innocence? Or...?