Tagger not showing tags or rendering assigned tags on backend

[vibedesign]

I noticed that the solution here does not fully solve the issue and @halftrainedharry fixed it in this thread:

Tagger: Group Sort Field Rank not displaying Tags

It turns out, the solution from the other thread was wrong. It should be: $c->sortby($this->modx->escape($sortField), $sortDir); (escape instead of quote.)