After ~ 3 hours on the phone with Meraki and sharing the information provided by @IDV , @Raphael, @dgander , @dade80vr & @dade80vr we have a "bandage" to resolve this until an update to fix it is released. I was informed that Meraki is aware of the issue and is working on a solution. No ETA as to when the actual fix will be known. Meraki also stated that this is only affecting MX84's. I suspect it may affect other models as well that the setting listed below is available on.
Solution: Disable Web Cache and reboot router.
Security & SD-WAN -> SD-WAN & Traffic Shaping
Unfortunately a reboot is required for the change to take effect.
I hope this helps anyone currently having the issue.