Riot internship: Lack of response follow-up

I submitted an internship application to Riot that they have not responded to, despite having submitted it two months ago and it now being passed their guaranteed-response date. I've been looking for some way to contact Riot to inquire about my application.

I've submitted a request to join the career LinkedIn group (currently pending), but I have yet to find a contact e-mail or phone number. Does anyone (particularly a Red) know how best to proceed?