The owner doesn't provide Softaculous for now due to cost constraints, however if you check your cpanel carefully there's another installation link for WordPress. It's in the same section under "Site Software". It's slightly less sophisticated than the one through Softaculous but it works well. I've installed and have been using that link. It's the WordPress installation package that comes through WHM/installation.
You need to click on the highlighted WordPress, and then afterwards it should come up with a scroll down that provides you the domains you have loaded on your panel. You then select a domain, and then follow through the installation steps.