The reason you couldn't find your media images on the storeFront is Magento system couldn't transfer your media image file from the database to the file system. Yes though you saved your media file in the database , when the browser requests for the media file, Magento will fetch the binary file in the database and transfer it to the file system apparently to return it back to the browser. As your file is not in the file system which magento expects it doesnt show up and no surprise catalog:images:resize command failed eventually.
To be precise,there's a file under yourmagentoroot/pub/get.php which is the PHP script responsible to transfer the files from the database to the file system to fulfill browser media request. The possible reason that it couldn't be was it might not be triggered at all because of another rewrite configuration setting
So just set your debug break points in your editor for get.php and confirm whether it's triggered.
Besides these, also make sure you enabled mod-rewrite in your webserver (apache/nginx) and the file permissions are set right.
Before that get yourself acquainted with How Magento stores the media in the database and how it renders from their official 2.x (2.3) docs.
Hope am pointing you to the right direction.
System locates media in database. A PHP script transfers the files
from the database to the file system, and sent to the customer’s
browser. The browser request for media triggers the script to run as
If web server rewrites are enabled for Magento and supported by the
server, the PHP script runs only when the requested media is not found
in the file system. If web server rewrites are disabled for Magento,
or not supported by the server, the PHP script runs anyway, even if
the required media is available in the file system.