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I am sorry to hear about this situation. On this website, I do not always get to give good news, and this is one of these times.
Unfortunately, they can request a servitude be recognized by the Court. Servitudes in Louisiana are akin to easements. See Louisiana Civil Code article 693:
Art. 693. Enclosed estate; voluntary act.
If an estate becomes enclosed as a result of a voluntary act or omission of its owner, the neighbors are not bound to furnish a passage to him or his successors.
If the property is truly landlocked, then the owner has a right to request a REASONABLE egress/ingress road. Now, what he may be requesting may not be reasonable and the Court may with the length/width/location of the path and make it smaller and more straight and narrow. However, he is likely to get the servitude request. And this is true even if the land has been subdivided (even by them) and there are covenants in place (not sure who told you otherwise).
The best argument one has here is to minimize the path that the party is requesting. And also note that it is not as though that they would OWN the path or could use it for anything else aside from egress/ingress.
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