Of course your loading times are long, WordPress is quite slow. And the more plugins and themes you use, the slower loads are. Also, the bigger the theme/plugin, the longer the load. And also FYI, cache plugins are discouraged here because of their high server resource usage and sort-of ineffectiveness on free hosting since we don’t have server-side cache enabled.
I have a few domains with rf.gd extensions and they load in less than 1/2 second.
And pinging our servers will not work because they are set up to block pings to protect the network infrastructure.
You may be able to set up a cron job on each of your websites to load /wp-cron.php every 15 minutes or so. Understanding Cron Job schedules