For miners that don't fully trust the displayed hashrate or that the communicated dev fee is correct, I would argue that the best way to verify poolside/dev fee hashrate is with fake pool hacks, much like the one we built ourselves for ethash, available on my github. It sets a low diff, the miner you want to test submits many many more shares compared to a normal pool, and after maybe 12h you have a very accurate picture of the "poolside" hashrate of the miner you're testing because you'll have submitted 500,000 shares by then and get a much much more accurate data point than looking at a 6h or 24h average on some pool for 1000 submitted shares (which really means nothing tbh).