As a test, choose one of the computers that has the problem.
Search for installations of the ‘missing’ font (“Mechanical” ?). There may be MORE than a single installation of the font of interest.
Excellent and VERY DETAILED guide:
‘https://www.digitalcitizen.life/view-install-remove-fonts-windows-10/’
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Try to learn of any font conflicts. Sometimes, there is another font, that might be involved, as a layer - under/over - and so, you do not see the font of interest.
Happened with a conflict between Arial and Helvetica neue - take a look at the following issue / topic and its replies:
‘Brave browser displaying thin fonts’
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Probably related:
Weird Blurry Fonts when Brave Shields Enabled’
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