Ask what happened between the released failure and the final acceptance, using one identifiable bracket if the records allow it. I would separate the correction operation, inspection work and waiting rather than put the whole elapsed gap into a box called rework.
You may discover that nobody timed the hands-on work. That is still a useful answer for purchasing: the allowance is unresolved and needs observation. A neat number copied from the final inspection timestamp would be easier to compare and much harder to defend.
Then the waiting belongs in the delivery picture even if it is not active correction cost. Does the proposed process depend on that same person and bench, or has the estimate assumed they will somehow be available whenever the robot finishes?
Put that dependency into the estimate now, with active work and waiting both unresolved where unmeasured; the production plan cannot borrow the same person's time twice just because one operation sits outside the robot drawing
Who will own the next decision when the study returns? I'd want purchasing, fabrication and inspection looking at the same route, rather than each pricing only the operation they recognise.