Good. Some progress there. It verifies that when you run 'create connection' it should run OK.
What OS platform your RS and DC are on ?
The replication flow is typically as follows :
PDS.PDB ==> RS ==> DC/ECDA ==> RDS.RDB
Primary Replicate
So test connection between each link first by hand and make sure that it works.
ON AIX Unix connector issue points to LIBPATH variable where it is not able to get the needed connector. E.g. for me the Oracle connector is in "/sybase/15/REP-15_5/connector/lib" folder in AIX.
I do not have MSSQL set up so can not help with exact scenario.
HTH
Avinash