HAProxy for Smart Proxies in different locations

Problem: I would like to get your opinion on the below scenario to see if it is possible at all to configure HAProxy on Smart Proxies that are deployed in different Sites (has different vlan) and i’m mainly looking for failover mechanism in case one of the smart proxies goes down, it should failover to the other

Assuming below sites are located in one region (west coast) but different sites
Smartproxy A has an IP (deployed in Site A)
Smartproxy B has an IP (deployed in Site B)
Smartproxy C has an IP (deployed in Site C)

Expected outcome:

Foreman and Proxy versions:

Foreman and Proxy plugin versions:

Distribution and version:

Other relevant data: