5-7: para esa fecha: by that time (date).
5-8: después de muerto: after (he is) dead.
5-9: de haber echado tan corto el plazo: for having set so near (lit. short) a time.
5-10: tomó el tole: departed hurriedly.
5-11: vamos: (imperative) and vaya (subjunctive) are often used, regardless of their original meaning, as mere interjections. Translate: come now, well, etc. Cf. French allons.