�Hola Camilus!
First of all, sorry so much for the delay... Busy days!
Ok, the conjugation of the verb "despertarse" is correct. And about the sentence:
"Ellas quieren encontrarse con nosotros"
1. Ellas quieren se encontrar con nosotros -->
This one isn't correct, as "se", used together with infinitives and imperatives, is always placed after the verb.
So, in your second option:
2. Ellas se quieren encontrar con nosotros
here, the sentence is correct, as "se" is placed before the verb, which is conjugated (and it isn't an imperative).
Hope it is clear! If not, please let me know, ok?
Finally, about your last question:
"Using the first person, would it be correct:
a. Yo quiero encontrarme con nosotros
or
b. Yo quiero me encontrar con nosotros
or
c. Yo me quiero encontrar con nosotros"
Here, you can see that in sentences a. and b. we can apply the same thing I told you before:
"se" always after the infinitive. So the correct sentence is <a.>.
And finally, sentence c. is correct, as the verb is conjugated (and, again, the verb is not conjugated in the imperative tense), so "se" is placed before the verb.
Let me know if this explanation helped you. Ok?
