Just a comment: placing your issue in Debugging & Dev Problem Solving - RedwoodJS Community led you to a long standing thread on Proposal: Testing and Debugging Project, which tries to get the Redwood users (as different from contributors / core team members) engage in writing RedwoodJS online documentation on Testing and Debugging (code named Tandem).
This comment is written to explain a possible lack of answers to your cache related question which is very more special than the notion of “testing and debugging” - for possible fear of falling in the document writing trap 