I recently made records in Vietnam in 5.1 also in the jungle. But 'Jungle' is a very wide term, so if you could be more specific, I can check if I have something for you.
For example the jungle in Vietnam was very misty and quiet and completely different for example to a jungle in brazil.
Also, if you are working now on the filmset, why are you not recording your own atmospheres? If the director wants it, so you have good reasons to go out and record them. If you can't record it in 5.1, record it it stereo. It's better to make a good stereo record than a bad 5.1 or nothing.
Stereo-tracks can be layered together to surround sound atmospheres, no problem. If you have recorded 5.1 atmsopheres, you can layer them with stereo sound to make it wide or make them sound like you want it.
If you are interested in my Vietnam jungle atmospheres, let me know. But I need to edit them first, they are raw now. You can contact me by my site: https://www.soundeffects.ch/