Modern,
ERIN and Danzick's advice above is excellent, though I think there may be some issues particular to Ambarella.
In my limited experience, Ambarella seed pods are incredibly woody and fibrous. There are five seed chambers buried underneath a mess of fiber and tough, matted 'hair'. In each chamber, there seems to be a single fragile seed, resembling a sunflower seed. I have tried several times to gently remove the seed from the pod, but I found it all but impossible to do without destroying the seeds in all that mess.
Here's a (bad) photo of the seed pod, after scraping away much of the fiber. Excuse my giant fingers:
As a result, in your case, what you probably have is two sprouts (from different seed chambers) growing THROUGH the tough, woody seed pod. Therein lies the problem; the sprout roots are not only intertwined, but are also connected by their woody seedpod. Until this pod decomposes, it's gonna be hard to separate the two.
There must be a reason for this pod design, but damned if I know. Maybe Mother Nature only wants the strongest seedling to survive.
If it were me, I'd just wait and let them both grow unless you have a definite reason to separate the two. Maybe you could dig down and see if the woody pod is easy to break apart? Who knows -- maybe it's already decomposed.
If you want to give separating them a shot, and accidentally end up killing your seedlings, then no worries. I've got another one with your name on it.