When Aiko is interviewing and exchanging information with Ayumi Shinozaki and Yoshiki Kishinuma, both survivors of the exact location she is researching on, she pulls out the Photo of Sayaka and asks the two if they knew her. When they both say no, Aiko looks disappointed and she puts it away.
Significant plot details end here.
Items in Corpse Party: Blood Drive
Do note that not all items appear in players inventory, some are only seen during cutscenes.