I have DHCPv6 configured on my Layer 3 Switch. PCs in the picture receive their IPv6 addresses and are able to be pinged with success from both same and different subnets.

However, when it comes to IoT devices (such as WEBCAM1 or WEBCAM2), they do not receive their IPv6 address from DHCPv6 using automatic configuration:

Then I thought that setting up a default gateway on IPv6 (using the command Switch(config)#ipv6 route ::/0 2027:017c:cede::1 as the subnet that WEBCAM1 is in is 2027:017c:cede::) could work so I could at least set it up statically, however, I'm unable to set it on the configuration of the device as my input is simply ignored:

As I'm trying to dual stack the network with IPv4 and IPv6, I was able to configure a default-router on IPv4, exclude it from the DHCPv4 list and assign it to IoT devices statically. However, it does not seem like this is possible with IPv6 or at least I don't see a way.
What could be the solution so I could ping IoT devices on IPv6?