Did the police make any attempts to validate their alibi by asking them independently what they did without battering them into speaking nonsense that the police wanted to hear?
Surely they asked them independently. Starting on Nov 2.
Later, however, when they contradicted each other, they started to avail themselves of the option of not responding.
It would be informative on these kind of issues if you could provide a link to a transcription of the police interviews of Sollecito and Knox.
Yes it would be informative.
Though I guess that all inconvenient parts would be immediately labelled "coerced".