The Government cannot arbitrarily withhold contract funds. There is a due process involved that consists of written rationale in the form of a proposed action but also gives contractors ample opportunity to state their case as to why that action should not be taken.
Source: PNWC’s Government Contracting Update: Notice of Intent to Disallow Costs
New Regulation Formalizes Ombudsman Practice and Identity for IDIQ Contracts
An ‘ombudsman’ is an official charged with addressing and/or investigating the interests of individuals’ or companies’