Varnish purging multiple servers

I’ve been using W3 for quite a while now, and just recently we noticed that it seems as if either W3 is no longer purging multiple servers or perhaps never has. It’s only recently come to light because one of my clients is making heavy changes to their images, which Varnish caches, and depending on which server it’s bouncing between via the load balancer it’s showing inconsistent crop results, due to one server purging and the others not.

Here’s a generic image of my setup:
https://cl.ly/image/0a1X0I2X2R0v

I’ve tested this multiple ways. In the following scenarios all I’m doing is swapping the order of the servers out of the text area or removing them:

Scenario 1:
server a <– purges
server b <– does not purge

Scenario 2:
server b <– purges
server a <– does not purge

Scenario 3:
server a <– purges

Scenario 4:
server b <– purges

So in each scenario only the first server will ever purge. I’ve verified the array inside the config as well and I do see all the servers listed, I’ve also turned on debugging and there’s no error that occurs in relation to varnish. In each instance I was running, varnishlog -c -m RxRequest:PURGE which will only show purge requests as they happen.

I’ve also tested another plugin: Multi-Varnish HTTP Purge which does purge both of them at the same time as expected, however, I don’t want to use another plugin to accomplish this

Let me know if you have any ideas or tricks I might be missing

https://www.ads-software.com/plugins/w3-total-cache/