Your narrative contains anachronisms since Amanda was safely ensconced in jail before bleach even became an issue in her case.
Bleach only became an issue AFTER Napoleoni and Donninoi had ground down on Amanda during the wee hours of Nov 6th, so those two dopes never would have thought to ask Amanda about bleach that night. This can be confirmed by checking the interrogation recordings from that night.
Bleach only became an issue when detectives searched Raffaele's apartment and claimed to have smelled bleach there, but it was only Lysoform detergent they smelled.
When they couldn't find incriminating DNA evidence against either Amanda or Raffaele in Meredith's bedroom, likely Stefanoni had informed the prosecution that bleach can destroy DNA, which then spawned all the subsequent nonsense about bleach receipts, and the such.
The prosecutors may have later questioned Amanda about bleach, but by that time Amanda had an attorney and she had long ago escaped undue pressure from Napoleoni and Donninoi in one of their inquisition rooms.