Hello! Welcome to the forum!
I am not sure if I totally understand the question.
You have a set of gauge blocks that you do not send out for periodic calibration-working standards. You verify these gauge blocks in-house with a higher order set of standards that are sent out for calibration-secondary standards. You use the secondary standards to verify instruments in your facility. Is that accurate?
As long as your secondary standards maintain traceability, then technically the instruments verified downstream from them also have traceability. Also important would be to assure you have adequately accounted for the collective uncertainties with the working standards and the in-house instruments that are being verified. You should assure adequate accuracy (or better, uncertainty) ratios are in-place.