Please use Iceberg's SparkSessionCatalog for accessing non-iceberg tables. I see that you are using AWS Glue catalog which goes well with SparkSessionCatalog.

org.apache.iceberg.spark.SparkSessionCatalog adds support for Iceberg tables to Spark's built-in catalog, and delegates to the built-in catalog for non-Iceberg tables

From: https://iceberg.apache.org/docs/1.9.1/spark-configuration/#catalog-configuration