Correct way of adding images programmatically?

I have the following problem, right now my program uploads the images and does it good, however when i go to the edit product page, the following are empty or uncheked:

• Role
• Alt text

Here is the code i use:

<?php

namespace Vendor\Module\Model\Adminhtml\Product\MediaGallery;

use \Magento\Catalog\Model\Product\Gallery\EntryFactory;
use \Magento\Catalog\Model\Product\Gallery\GalleryManagement;
use \Magento\Framework\Api\ImageContentFactory;

class ImageUpload extends \Magento\Framework\App\Helper\AbstractHelper
{

/**
 * @var \Magento\Catalog\Model\Product\Gallery\EntryFactory
 */
private $mediaGalleryEntryFactory;


/**
 * @var \Magento\Catalog\Model\Product\Gallery\GalleryManagement
 */
private $mediaGalleryManagement;


/**
 * @var \Magento\Framework\Api\ImageContentFactory
 */
private $imageContentFactory;


/**
 * @param \Magento\Catalog\Model\Product\Gallery\EntryFactory $mediaGalleryEntryFactory
 * @param \Magento\Catalog\Model\Product\Gallery\GalleryManagement $mediaGalleryManagement
 * @param \Magento\Framework\Api\ImageContentFactory $imageContentFactory
 */
public function __construct(
    EntryFactory $mediaGalleryEntryFactory,
    GalleryManagement $mediaGalleryManagement,
    ImageContentFactory $imageContentFactory
)
{
    $this->mediaGalleryEntryFactory = $mediaGalleryEntryFactory;
    $this->mediaGalleryManagement = $mediaGalleryManagement;
    $this->imageContentFactory = $imageContentFactory;
}


/**
 * @param string $filePath
 * @param string $sku
 */
public function processMediaGalleryEntry($filePath, $sku, $productName, $additional = false, $position = 0)
{
    $entry = $this->mediaGalleryEntryFactory->create();

    $entry->setFile($filePath)
        ->setMediaType('image')
        ->setDisabled(false)
        ->setLabel($productName);

    if($additional)
    {
        $entry->setPosition($position);
        $entry->setTypes(['thumbnail']);
    }
    else
    {
        $entry->setTypes(['thumbnail', 'image', 'small_image']);
        $entry->setPosition($position);
    }

    $imageContent = $this->imageContentFactory->create();

    $imageContent->setType(mime_content_type($filePath))
        ->setName($productName)
        ->setBase64EncodedData(base64_encode(file_get_contents($filePath)));

    $entry->setContent($imageContent);

    $this->mediaGalleryManagement->create($sku, $entry);

}

}

What happens in edit page is this: