If you think a migration might have gone awry, then maybe your web how would be best suited to help you resolve this.
If you don't remember installing WortdPress twice (in two different locations), then it's quite possibly a migration problem.
You certainly seem to have two different login URLs:
... which suggests to me that you have two different installations.
Your current redirect ensures that the site seen by the public is always the root directory site (not the /wordpress/ one).
This suggests that it's the root site that you should be using but I don't know which one you've recently been logging into.
Unfortunately, I have no knowledge of the history of your site (whether a second installation was intentional or a migration ever took place) or access to your web server.
With this in mind, I think your web host would be better placed to help you untangle things.
Here are a couple of things you could check to see if things make sense:
(1) Check /wp-config.php and /wordpress/wp-config.php to see if both installations are using the same database and/or table prefix. Look for:
define('DB_NAME', ...);
$table_prefix = 'wp_...';
(2) Check /wp-config.php and /wordpress/wp-config.php to see if the path to the content directory (the parent directory for the uploads directory where Juicebox stores its XML files) is explicitly defined. Look for:
In a regular installation, this constant will not be present (and WordPress will just use the default value of ABSPATH . '/wp-content'). However, the path can be overridden with WP_CONTENT_DIR so it might be interesting to see if one installation has an explicit entry for WP_CONTENT_DIR.
You might be able to 'fix' your problem by setting a WP_CONTENT_DIR in the wp-config.php file in one of your installations to force a certain content directory to be used.
e.g.
define('WP_CONTENT_DIR', $_SERVER['DOCUMENT_ROOT'] . '/wp-content');
... or:
define('WP_CONTENT_DIR', $_SERVER['DOCUMENT_ROOT'] . '/wordpress/wp-content');
However, with your two installations seemingly intertwined, I don't know which installation you should target for this 'fix' or which path to use.
(Also, I put 'fix' in quotes as this is more of a potential workaround than a true fix as, under normal circumstances, you shouldn't need to define a WP-CONTENT_DIR and you'll still be left with two installations on your server.)
Maybe you'd get more specialized help from a WordPress forum or more knowledgeable support from your web host (as they will have access to everything and might have been involved in the installation and/or migration). These are avenues I'd certainly explore.
Incidentally, there won't be a queue. There will be one content directory specified per installation and either it will be used or saving content will simply fail. As noted above, the default path will be used unless WP_CONTENT_DIR is specified.