Why doesn't the file connected via include see the variables?

Question

CodeIgniter

PHP Version 7.2.19-0ubuntu0.18.04.2
Linux ubuntu-s-1vcpu-1gb-fra1-01 4.15.0-65-generic #74-Ubuntu SMP Tue Sep 17 17:06:04 UTC 2019 x86_64
Site on Codeigniter 3 After the transfer, it stopped displaying data. That is, the template is displayed, but there is no information from the database. I got to the Loader.php file, which contains the following lines:
extract($this->_ci_cached_vars); - here it is clear - Imports variables from an array. Checked up - variables are imported. For example print_r($slider); prints the required information.
ob_start();
include($_ci_path); - we include a file that uses imported variables, for example:
<? if (isset($slider) && sizeof($slider)) { print_r($slider); }?>
Nothing is printed as a result. Why does the included code not see the variables?