If both the Catalog and the Schema and tables are stored externally, and you have deleted the original catalog, you should be able to recreate the schema in a new catalog by pointing it to the previous data files and running the SYNC command. Here are the steps .
1. Define an External Location in the new catalog that points to the same location where your previous data files are stored. Sounds like you did this.
2. Use the SYNC command to create a new Unity Catalog table based on your legacy table location. This will only create metadata and not change the underlying data. The syntax is as follows:

SYNC hive_metastore.schema.table uc_catalog.schema.table This command will create a new table in your new catalog that points to the same data files as your old table.  It sounds like you may not have done this.

Note that the SYNC command assumes that the data files are still in the same location and have not been moved or deleted. If the data files have been moved, you will need to adjust the External Location accordingly.

Hope this is helpful.

I have an issue when trying to create a new catalog based on the previous catalog location : 

Any idea ? Thanks Scott ! 

Hi,

Looks like you are creating the catalog at the container level. Are there any other UC objects created pointing to that? Is the external location created at the container level? Can you please have a look at this and see if there is overlapping? Thanks!