SMB shares names appear as all lowercase regardless of how their name is formatted.
To reproduce the issue:
Create a share with a name which contains uppercase characters:
zfs create -o sharesmb=name=TestShare rpool/testshare
Connect to the SMB server from a Mac client without specifying any share my name.  You will be presented with a list of shares, all of which will be lowercase.

Share names are now listed in the correct case.  Specifying the share name still works even if the case is wrong.