Always only one of two IP addresses as response

Hello forum,

My colleagues are using a learning platform. Unfortunately, the provider is having a problem. There are two IP addresses under the URL, which appear to be randomly assigned. One of the IP addresses is unreachable. What do I need to do with the SSLO to access only one of the IPs via our proxy chain?

I imagine it would be like this: when the user visits xyz.com, they always get the 1.2.3.4 IP address in response, not the 5.6.7.8. 

Is that possible?