My fault for not reading more closely. @jersonjunior already answered this in the above thread.
exten => s,1,Progress()
same => n,Set(audio=${SHELL(node /opt/aws-nodejs-sample/script.js --mp3=/home/asterisk/audio-${cpf}.mp3 --text=’${nome}’ --wav=/var/lib/asterisk/sounds/audio-${cpf})})
same => n,Playback(audio-${cpf})
Replacing the Playback with Background does the trick. On the fly recordings that are customer interruptible.