Multiple Application server on diffferent LAN - Topology

One of our client is building multiple application servers with 1 JTS server and testing their topology.
It seems to be working but there is some concern for this topology.
If you have any advice for this topology, please let me know.

As you can see they have
Server 1 : /jts , /admin
Server A: /ccm , /qm
Server B: /ccm, /qm
* Server 1 <=> Server A , Server 1 <=> Server B but Server A and Server B is different LAN, so no communication.

-> they were able to finalize all application on Server A and Server B but we get this error but able to finalize.
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Error message in English:                                              
CRJCA0003E The Lifecycle Project Administration (LPA) application made a
 request that was answered by an unexpected response code. The request 
was: https://.../ccm/clmSampleProject. The response was: HTTP/1.1 400 
Bad Request.                                                     
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