I would probably have made customers a custom post type, with projects related to customers and customers being in an industry, that would come with its own set of problems.
saving and loading terms won’t work because in WP, terms can’t have terms.
The way you’re doing in is that you’ll need to get the list projects, get the customer terms and then loop through them to get the values from the ACF industry taxonomy field on each customer term in order to display them.
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