Have Custom Taxonomy Slug Fall Under Custom Post Type Slug

You can do that by writing a function using the ‘generate_rewrite_rules’ WordPress hook. https://developer.wordpress.org/reference/hooks/generate_rewrite_rules/

<?php

function guides_cpt_generating_rule($wp_rewrite) {
    $rules = array();
    $terms = get_terms( array(
        'taxonomy' => 'venue-type',
        'hide_empty' => false,
    ) );
   
    $post_type="guide";

    foreach ($terms as $term) {    
                
        $rules['guide/' . $term->slug . '/([^/]*)$'] = 'index.php?post_type=" . $post_type. "&guide_post_type=$matches[1]&name=$matches[1]';
                        
    }

    // merge with global rules
    $wp_rewrite->rules = $rules + $wp_rewrite->rules;
}
add_filter('generate_rewrite_rules', 'guides_cpt_generating_rule');