Whistleblower Expansion Act of 2019 This bill specifically applies to subcontractors and subgrantees certain whistleblower protection provisions regarding contractor protection from reprisals. Such reprisals are for disclosure of information reasonably believed to evidence gross mismanagement of a federal contract or grant, a gross waste of federal funds, abuse of authority relating to a federal contract or grant, a substantial and specific danger to public health or safety, or a violation of law, rule, or regulation related to a federal contract or grant.