IP restriction breaking integrations and connections like Slack

I want to enable IP restriction to improve the instance security - but I've hit a roadblock…

Slack does not support static IP on their outgoing IP ranges (nor do other apps that rely on AWS) . This means i'm not able to enable the restriction without severely impacting integrations and connections. 
 

Two options are to: 
1. Split the ip restriction for API and UI
2. Allow specific endpoints to be excluded from the restriction

Has anyone found a way around this? a proxy will not help as i am using slack native Zendesk integration in wrokflows