I've read somewhere that units of measurement weren't totally standardized at the time. It came up talking about how the stories of Napoleon being short weren't really true, he was an average height, but with the French units of measurement were slightly longer so the numbers were lower, so it would sound like he was short to someone that only knew the english measurements, and the English just used that for propaganda.
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https://www.thoughtco.com/was-napoleon-bonaparte-short-1221108
http://www.todayifoundout.com/index.php/2010/03/napolean-bonaparte-having-been-short-is-a-myth/
https://www.entitymag.com/napoleons-height-history/
had some time this afternoon and found a couple of links. Not the most academic sources, but will serve for the purposes of this discussion that model figures can very by several mm and still be considered accurate to scale since measurements weren't exactly as accurate as they are today. If there is debate over someone like Napoleon's height, then exact measurements of any other historic figure can be taken with a grain of salt.