Taxonomy i18n does not translate term name in a term page
This is a known issue: Vocabulary Name value doesn't get translated. It dates from 2005 (!), related to D6, status "won't fix". However comment # 2 in that issue states:


  I have used the locale module to translate the name of the vocabulary, and display it with t($vocabulary->name). If all modules would display the name this way (e.g. taxonomy_menu does it), then there is no need for a new database table i18n_vocabulary.


The t($vocabulary->name) seems like a possible/partial work around to consider, i.e. from within a (custom) module.

There is a more recent similar issue, i.e. Vocabulary names are not translated. That one is for D7, with status "needs work".

Another potential work around could be to have a separate taxonomy for each language (and with a "name" corresponding to that language). Of course, you'd have to think how to best use these separated taxonomies for each content type (a kind of "solution to the problem, changes the problem) ... 

That's probably the best you can get these days. Does this somehow "answer the question"?