Trouble from installing LifterLMS

I installed LifterLMS yesterday to my subdomain:http://membership.darylochs.com/index.php/174-2/
At the conclusion of installation when I clicked on Activate, I received this message at the page-top:

Fatal error: Call to undefined method PucFactory::addVersion() in /home4/dlochs/public_html/membership/wp-content/plugins/InstaMember/sources/plugin-updates/plugin-update-checker.php on line 1051

From that point on I cannot access this site. I was referred to “Plugin Update Checker” but that made no sense to me even though I used the code insertion mentioned there.

At this point I am locked out of my site, cannot figure out from my hosting File Manager how to uninstall what’s there – if anything. And LifterLMS offers no assistance unless I purchase the PRO version.

Can you provide any relief?
Thank you,
Daryl Ochs

https://ww.wp.xz.cn/plugins/lifterlms/