YOU SAID:

she sat up late worrying lest he be murdered on the way home

INTO JAPANESE

彼女は帰りに彼が殺されないように心配して夜更かしした

BACK INTO ENGLISH

She stayed up late worrying that he wouldn't be killed on the way home.

INTO JAPANESE

彼女は帰りに彼が殺されないようにと心配しながら夜更かしをした。

BACK INTO ENGLISH

She stayed up late worrying that he might be killed on the way home.

INTO JAPANESE

彼女は帰りに彼が殺されるのではないかと心配して夜更かしした.

BACK INTO ENGLISH

She stayed up late worrying that he might be killed on the way home.