0800jukebox on "[Plugin: Boopis WooCommerce RFQ] 500 error after woocommerce update"

Hi David,
I tried removing mprfq & formbuilder, removed the plugin and reinstalled still the same, I couldn't see the link being called so I tried

//Mod echo "<button type=\"submit\" class=\"single_add_to_quote_button button alt\">" . apply_filters('single_add_to_cart_text', __( 'Inquire', 'boopis-woocommerce-rfq' ), $product->product_type) . "</button>";

$link = '<a href="'.esc_url( remove_query_arg( 'added-to-quote', add_query_arg( 'add-to-quote', $product->id ) ) ).'" rel="nofollow" data-product_id="'.$product->id.'" data-product_sku="'.$product->get_sku().'" class="button add_to_quote_button product_type_'.$product->product_type.'">' . __( "Inquire", "boopis-woocommerce-rfq" ) .'</a>';
echo "$link";
// end mod

and that works...for now