日本人をよく理解しようと一生懸命な人もいます
I don't understand the function of this particle in this sentence. this sentence could be translated as: "there are also dedicated people that want to understand better Japanese people"?
Here is an answer that has the explanation of that usage of the particle with this usage: https://japanese.stackexchange.com/a/47519/22133
Basically it is a quotation of someone's speech or thoughts without the words 言う or 思う. You could translate the sentence like this
There are also (even) dedicated people who think "Let's understand Japanese people well".
This is pretty awkward in English, but it gets across the idea that the people are thinking what comes before the と. Your translation is probably better because it gives off the same meaning and is less strange.