Siebel Full Sync And Asynch Migration Fails At "Import" Step When Using Reverse Proxy REST URL Using Siebel Migration Application (SMA) (Doc ID 2748313.1)

[DEBUG] 2021-01-08 13:46:13.816 [https-jsse-nio-9001-exec-6] Migration - com.siebel.migration.server.MigrationUtility:InvokeRestCall Response received from RST URL: https://<reverseproxyURL>:port/siebel/v1.0/service/ExecutionDataService/Delete
[DEBUG] 2021-01-08 13:46:13.816 [https-jsse-nio-9001-exec-6] Migration - com.siebel.migration.server.MigrationUtility:InvokeRestCall Response from Server: {"SiebelMessage":{"IntObjectFormat":"Siebel Hierarchical","MessageId":"","IntObjectName":"Transaction","MessageType":"Integration Object","Transaction":{"status":"Running","Id":"1-20COJVN","mgPlanName":"Asynch_FullRR_Import","mgPlanId":"1-1Z51XT7","TransactionResource":{"seq_num":"6","Id":"1-20COJVT","resName":"Migration Application Workspace Data Service","status":"Not Started","endTime":"","loglocation":"https://<reverseproxyURL>:9001\/siebel\/v1.0","txnId":"1-20COJVN","stDate":"","operationName":"SeedCopyImport","resType":"DB Util","trackingId":"","resId":"1-1Z51XTA"}}}}
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[TRACE] 2021-01-08 13:46:13.817 [https-jsse-nio-9001-exec-6] Migration - com.siebel.migration.server.MigrationServer:doPost Output message: {"status":"error","msg":"Could not unpackage the zip file due to Unable to get the Siebel FS path from REST URL
https:https://<reverseproxyURL>:PORT/v1.0\/MigrationFilePrepareAndDeploy\/preparePackage Context Path \/siebel due to exception: java.lang.Exception: Unable to get the File System path due to error REST URL https:https://<reverseproxyURL>/v1.0\/service\/Application Migration Utility Service\/GetFileSystemPath returned the HTTP code 401 and the response is <title>401 - Unauthorized: Access is denied due to invalid credentials.<\/title><style type=\"text\/css\">
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<h2>401 - Unauthorized: Access is denied due to invalid credentials.<\/h2>  <h3>You do not have permission to view this directory or page using the credentials that you supplied.<\/h3> <\/fieldset><\/div><\/div><\/body><\/html>. File System path is empty. "}