What happens to licenses if ID is missing but a concrete5 site

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What happened to the existing license of the site if the previous webmaster disappeared.

A Japanese company took over a concrete5 site. New webmaster was able to obtain the admin access to the concrete5 site.

However, they don't have concrete5.org ID on file... the previous webmaster guys disappeared.

So what's the best solution for this circumstances?
What should they do for their add-ons?

Thanks

katz515