Want to be communicated by AWS policy through a specific proxy server

Products

• CA Privileged Access Manager - Cloakware Password Authority (PA)
• CA Privileged Access Manager (PAM)

Issue/Introduction

From the PAM that placed in the private subnet, when the AWS policy configuration is set, it seems PAM communicates with the sts.amazonaws.com. In order to communicate with sts.amazonaws.com, is it possible to through a specific proxy server. For example, in the below flow, PAM through the "Proxy Server A" to communicate the sts.amazonaws.com.
 

PAM ====> Proxy Server A ====> sts.amazonaws.com

Is it possible to do that by the PAM's feature? 

Environment

CA Privileged Access Manager 3.x (PAM)

Resolution

There is not the expected feature in PAM.