Tanzania Safari & Snorkling what camera gear dhould I bring?

So I've booked a Safari trip to Tanzania with a couple days Zanzibar to go snorkeling and relaxing
As a hobby photographer I struggle with what gear I should bring, I have the option to hire a big-ass telelens but I'm worried I cant leave it in the hotel on Zanzibar in a safe place (probably won't fit in the standard hotel safe. Another option is a smaller telelens with an extender maybe, but that one has no stabilizer function
Or maybe I don't even need too much zoom? Can you get closer or just as close to wildlife as in the Krugerparc in South Africa?
I know there are more photographesr here so what would you bring and does anybody have experience with safari photography in Tanzania in general
Please share some tips!

I went on safari with my 12 year old granddaughter in 2018. I had two Canon cameras. I gave my granddaughter the 100-300 lens and she got wonderful photos with it. I also had an 18-175 lens which wasn't quite enough for distance shots of leopard etc., although I did OK with it. Her leopard photos are in this section of the blog. Note: The photos have been edited - cropped and straightened and sometimes brightened.

The lenses were mostly on the cameras all the time so if we were out somewhere, the cameras were with us. We were staying in tents and cabins and there weren't any safes, and I had my laptop with me which wouldn't have fitted anyway. I did not stay in any actual city hotels, so I can't speak to that. I did ship the camera's home in my checked luggage, and they arrived OK.

[ Edit: Edited on 13-Mar-2020, 20:02 GMT by greatgrandmaR ]

Thanks RosalieAnn, I'm also going camping most of the trip, I'm not worried for my gear that part of the trip as I will be carrying my camera most of the time, it's just the snorkling part where I have to leave my gear somewhere safe. Good to hear a 100-300 will do, thats what I was planning to bring and an extender to make it times 2 if needed so I guess I can leave the big one at home (one worry and a lot of weight less) Great shots on your blog, I hope I can make my big 5 complete, didn't catch the big cats in South Africa

I knew that it was the snorkeling part that you were worried about but I don't really have any information about that. Glad to help with the rest. I don't think my 100-300 lens is too big for a hotel safe.

I have only used one of the great big lenses once and that was a long time ago. It was unweildy.

We saw all 5 but the rhinos were a long way away.