B31.3 contains Sport Radiography for quality control purpose. I do not see the same Note in B31.3 but in ASME VIII-1 UW-52 it is well explained.

UW-52 SPOT EXAMINATION OF WELDED JOINTS
NOTE: Spot radiographing of a welded joint is recognized as an effective
inspection tool. The spot radiography rules are also considered
to be an aid to quality control. Spot radiographs made directly after a
welder or an operator has completed a unit of weld proves that the
work is or is not being done in accordance with a satisfactory procedure.
If the work is unsatisfactory, corrective steps can then be taken
to improve the welding in the subsequent units, which unquestionably
will improve the weld quality.

The concept is that the spot RT must give feedback to the welder as early as possible for necessary "corrective" actions to avoid the repeated mistakes.

I have encountered cases that people can not tell the difference between "correction" and "corrective action" which is well explaned in ISO 9000.

The welder who failed the RT does not have to always repair his own bad welds (correction) but it make the spot RT "out of control" if the welder does not receive any feedback of the RT for root cause and improvement (corrective actions).

The best answer to this question is not yes or no but a balance saying "Due to the fabrication plan the original welder is not required to repair his own defective welds but there is management measure in place such as welder's defect rate review and requailification for the welder's performance."