7x12 Sonny Boy

I can understand him not shooting Strand. The sound of the gunshot would attract other members of the tower. Are we to believe that Dorie knocked out Strand with a blow to the head and then had time to:
i. Gather up and wear all the armoured clothing that Howard just happened to collect?
ii. Take the baby through the tower without attracting the attention of any other residents and meet up with his co-conspirators?
iii. Say his goodbyes to his co-conspirators?
iv. Record a duet of Sonny Boy with Grace for him to play to Mo while pushing his way through the dead? and
v. Manage to get outside the border and part way across before Strand & Co even managed to spot him?
Hmm! I’ve seen some dodgy scripts during the series but this is just going downhill fast.