At this point I would say let it grow out for a little while and see what happens. Its so young at this stage that it could clear up on its own once those leaves grow out a bit. It could also be remnants from the seed casing or some part of it?
Most definitely will I let it grow out and more younglings I have. Curiously there were others I helped out such as a double embryo. The dormant one wrapped around and almost strangled the good one until I removed it here - https://www.420magazine.com/gallery/data/504/Dbl_Embryo.jpg
And the seed shell of another was clamped around the young head like a helmet. It is a small batch but all are doing fine now.