How to list file keys in Databricks dbfs **without** dbutils

Apparently dbutils cannot be used in cmd-line spark-submits, you must use Jar Jobs for that, but I MUST use spark-submit style jobs due to other requirements, yet still have a need to list and iterate over file keys in dbfs to make some decisions about which files to use as input to a process...

Using scala, what lib in spark or hadoop can I use to retrieve a list of dbfs:/filekeys of a particular pattern?

import org.apache.hadoop.fs.Path
import org.apache.spark.sql.SparkSession

def ls(sparkSession: SparkSession, inputDir: String): Seq[String] = {
  println(s"FileUtils.ls path: $inputDir")
  val path = new Path(inputDir)
  val fs = path.getFileSystem(sparkSession.sparkContext.hadoopConfiguration)
  val fileStatuses = fs.listStatus(path)
  fileStatuses.filter(_.isFile).map(_.getPath).map(_.getName).toSeq
}

Using the above, if I pass in a partial key prefix like dbfs:/mnt/path/to/folder while the following keys are present in said "folder":

• /mnt/path/to/folder/file1.csv
• /mnt/path/to/folder/file2.csv

I get dbfs:/mnt/path/to/folder is not a directory when it hits val path = new Path(inputDir)