The portal from gadomancy doesn't take you to the dimension so you cannot unlock the research in the outer lands, so even with a pearl, the "Shard of Creation" stays locked.
the easiest way would be to use ModTweaker to remove the Parent research "Enterouter", as this is the research the code needs to be completed before the shard unlocks as well. Edit: The gadomancy portal wouldn't even bring you to the "real" outerlands, it has a new dimension for that, so i guess you wouldnt even get the research if it worked... Edit: The Thaumcraft outerlands have the Dim-ID: -73 The Gadomancy outerlands have the Dim-ID: -42 Edit (again): I just tested: If you go to the Gadomancy outerlands you won't get the research!
Closing issue due to being resolved / Issue no longer valid / Lack of comment from O.P. Need mods to update, this is outside of MyM control.