After all your remedial information has been submitted to DoDMERB it will take anywhere between 4 weeks to 4 month for a waiver determination. The time depends on the complexity of the remedial review and backlog and availability of the waiver authority. The process to submit remedial information or getting remedial testing completed is mostly within your control. How long will it take you to get all the requested doctor reports together and/or schedule and complete the requested testing.
The DoDMERB website has flowcharts for the process and a FAQ that can provide additional information.