That contains a phrase: {xen:phrase you_can_earn_trophies_by_carrying_out_different_actions}
That'll need to be changed.
What else specifically hasn't changed? The rest of the Help content to do with Trophies seems phrased with the usual {xen:phrase trophy} and {xen:phrase trophies} phrases.
EDIT: Oh and {xen:phrase no_trophies_have_been_created_yet} but probably not relevant.
I'm an idiot as usual. I double checked and I didn't change the string as I thought. I noticed it was teh same word, so I filtered for it. It was bright red, so I assumed I changed it. However, when I actually viewed it, I hadn't changed it.