If a static IP on wan2, it's probably nothing to do with WAN LLB. Does the random disconnects happen when user is not operating at the machine or it suddenly disconnect when the user is actively operating something at the machine? If the former, there was a conversation in the forum about session-timeout with Citrix a while ago. And multiple solutions were exchanged. But the best answer was to set up Citrix's built-in keepalive to keep the sessions up. You can search in this forum.
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