Update - Meraki Support helped me troubleshoot some more items today and did some backend (non-client facing) items.  The CPU is running up to 100% usage and seems to be a hardware problem.  They have offered to replace the device as the next step as there may not be a solution.  ... View more

You're spot on. The general process would be: - Create new vlan - Exclude the new vlan from site-to-site VPN - Create L3 firewall rules blocking communication from the new vlan to your existing one. This can be any explicit deny rule with the source of the new subnet and a destination of the existing one, or simple a rule denying all 3 private IP ranges from the new subnet (for easy future proofing). - Connect wife's PC to new vlan with an access port ... View more