I want to be able to track every single reimbursable bill to its respective invoice line.”

I fully understand the Request.

You can run reports to see if what you Incurred for that customer has been charged back to them, or still is unbilled, or got marked Not Billable, in error.

There also […]

Resolution for 'corresponding issue: 'Is there any report showing the list of bills with the payment status of corresponding customer invoices' available: Yes.

The corresponding issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the corresponding issue yourself by looking for a resolution described in the article. If it is a complex corresponding issue or you are unable to solve the issue, you may contact us by clicking here or by using other corresponding support options.

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