The root of my problem was none of the above and it was a change in the way WordPress internal variables worked.
The plug-in I was attempting to troubleshoot was utilizing the following:
define('WPA_PLUGIN_DIR', WP_PLUGIN_DIR . "https://wordpress.stackexchange.com/" . WPA_PLUGIN_NAME);
define('WPA_PLUGIN_URL', WP_PLUGIN_URL . "https://wordpress.stackexchange.com/" . WPA_PLUGIN_NAME);
New Code which per these two links stating to do not use the internal WordPress variables and to use these instead took care of it in the primary plugin PHP file.
define('WPA_PLUGIN_DIR', plugin_dir_path( __FILE__ ));
define('WPA_PLUGIN_URL', plugin_dir_url( __FILE__ ));
Checking the WordPress codex was what I needed to do to determine methods were being used and the forums were helpful. I since found several plugins I previously stopped using due to SSL issues were doing something similar.