Filter through custom taxonomy with an array of taxonomy IDs

First, you can’t enter such expression as second argument in get_term(). Enter directly the name of your taxonomy…
Are you dealing with simple post categories? If that’s the case, your taxonomy name is 'category'.

$context['single_term'] = get_term( $user_terms_array[1], 'category' );

Second, ensure that $user_terms_array contains term IDs as integer.

$user_terms_array = array_map( 'intval', explode( '-', $user_terms ) );

Then, you’re on the good way. Using WP_Term_Query instead of get_term() wouldn’t give you any pros if I refer to the supplied info. In this context, I’d stick with get_term().