GSCoC 2018 / 'Attachments enhancements'

SO i read the AttachmentsService ahead of REST API work (ATT-24) thread and here is the first question come to my mind when i check the implementation. Please correct if i am wrong.

There are 3 methods implemented in AttachmentsServiceImpl for get the attachments based on the encounters and visits. So inside that Dileka used getConceptComplexList() method for only fetch the complex obs , which coded by the concepts configured through the module. So that means from the API we can get only the obs relevant to this module. Am i correct? Is there anything to implement or modify inside that methods?