...Terence Quinn is a British physicist who spent many years studying gravity and was emeritus director of the International Bureau of Weights and Measures. If he says it, it's golden.
Okay great, he said this in a nature piece:
"Who needs a more accurate numerical value of G (the current recommended value is 6.67408 ± 0.00031 × 10−11 kg−1 m3 s−2)? The short answer is, nobody, for the moment..."
https://www.nature.com/articles/nphys3651?proof=t
I guess were done here?
Here is his quote:
"Who needs a more accurate numerical value of G (the current recommended value6 is 6.67408 ± 0.00031 × 10−11 kg−1 m3 s−2)? The short answer is, nobody, for the moment, but being apparently unable to converge on a value for G undermines our confidence in the metrology of small forces. Although it is true that the orbits of the planets depend on the product of G and the mass of the Sun — the structures of all astrophysical objects are determined by the balance of gravity and other forces produced by, for example, gas, photon or degeneracy pressure — ab initio models of the Sun are still an order of magnitude away from predicting a value of G at a level comparable with laboratory determinations. We do not need a value of G to test for departures from the inverse square law or the equivalence principle. There is as yet no prospect of a theory of quantum gravity that would predict a value for G that could be tested by experiment."
The part you cut out after "nobody for the moment..." says that this value undermines their science in the metrology of small forces. He clearly suggests the recommended range is invalid and questionable there, rather than your suggestion that he is supporting it wholeheartedly. This is another point against you.
Trivializing the need for G doesn't directly address the matter of whether he thinks that he measured it. He is talking about the practical purpose for the such a measurement, in non-cavendish situations and measurements. He is correct that G is not needed for the equivalence principle tests. That's something else, showing that gravity does not depart on various ranges and situations from the concept that the Earth is accelerating upwards. The EP tests are highly and accurately verified.
Quinn's "we should be able to measure gravity" statement says that he cannot measure gravity in the Cavendish Experiment. In the quote you referenced we see a statement that the recommended range undermines their science in the metrology of small forces, showing that he is certainly not endorsing it. You're right. We are done here. We have talked about this for pages and you are still unable to substantiate your argument.