If you need voice actor's I would recommend using a (free) website called
Castingcall.club to find them. I don't think age is the main issue in regards to finding non-questionable individuals to work with online. (However I suggest still keeping an age limit of 17-18 as oldest since 18-19 is usually considered an adult.)
If you want to find people who are good writers, professional, and committed to a project than typically it's best to find someone a bit older to join the team. Even if it's just by a few years, if they know more about writing then they can help improve the quality a lot. Perhaps try to find a team of writers your own age that you can write and collaborate with for the most part and then find a few people who may not be as committed but they can read over and help edit and review the story.
From my experience the best way to find people (specifically voice actors) who are committed to a project and looking at it from a professional aspect is by creating a good casting call (a casting call is how you request for people to send you auditions for a role). Followed by managing your own level of professionalism. The best directors I've ever worked with were the ones who were professional, valued quality, and were committed to their own projects.
If you set the bar than others will match it. So if you don't want older guys pursuing you, than the best way to avoid that possibility is by
keeping a business level of space. Your relationship with them is essentially as boss and employee (though keep in mind that volunteer's deserve more respect since their time is being lent). Don't share anything personal, including your emotions. Maintain a business relationship and you should be fine.
PS If you're using google docs than perhaps use a backup Gmail account that you also use for your YT account. Gmail also has a built in feature called Google Hangouts that could be helpful for calling writers while working on the script.
You can use Castingcall.Clubs built in feature for communicating with voice actors or anyone else you hire from the site.
Hopefully this wasn't too much text for you and you will find some of this information useful! If you want any help using CCC or have some questions I'd be happy to help~
(Best way to contact me is by sending me a message on
my CCC account since I'm not on PMC very often.)
Just stay safe and be careful who you talk to, alright?
Heres what I have so far, I still need to shade it though
