I heard back from Disney yesterday!
"Currently, there are seven females and three males in the Safi River:
Panchita (F) is 23
Mezcal (F)is 27
Hans(M) is 20
Henry (M)is 26
Nacho (M) is 23
Tequila (F) is almost 29
Ramona (F) is 23.
Viviana, our oldest lady, is 46
Tuma (F) is almost 25 and just gave birth to Greta (F), who is just over one month!"
As a side note, this is definitely one of the most pleasant email interactions I've ever had with a zoological facility

I'm used to zoos responding to inquiries with varying degrees of wariness and giving as little information as they can get by with, if they even respond at all -- this team member was enthusiastic from the start and kept me updated along the way as she retrieved the information for me. She even tried to include a picture of mom Tuma and baby Greta which unfortunately didn't make it across, but I loved the excitement! Now that's an idea for a thread, rate each zoo's public relations teams