If you are actually feeding the part to the server via the ServerEnterAdd node, but when you try to get this part from this node on the server side it returns nothing, that would mean a bug in the engine’s replication which I find very unlikely.
Are you 100% sure you’re actually feeding the part to the node? Do this test just like I did in these pics below. I’ve placed a node to print the name of the part being fed on the client side and another node to print the same part on the receiving part (server side). Note that when I start adding the canted rail it’s name gets printed twice, once labeled as client and once labeled as server, meaning it was sent and received:
