helping without all information is not easy.

part of the Information shown.
For me that Lab is 7.8 in testoutapp.
the Terminal gives you back as result:
interface: 10.11.2.102
10.11.2.1 00-15-5d-01-
98-03
10.11.2.2 00-15-5d-01-
99-03
10.11.2.103 00-15-5d-01-66-64
10.11.2.255 (Broadcast)
224.* (4 different IPs)
239.255.255.250
255.255.255.255(Broadcast)
The Answers:
10.11.2.1
10.11.2.2
10.11.2.5 (not listed, not replying)
10.11.2.100 (not listed in arp)
10.11.2.103 (not listed in arp)
10.11.2.255 (Broadcast, can`t be)
The Graphic shows that 10.11.2.0/4 is Bulding A Floor 1 with DHCP and
.x ITAdmin
.y Office
common sense says the first or last available IP adress is the Router IP.
That would be 10.11.2.1-.
ipconfig says gateway is 10.11.2.5 (for whatever reason). (and not replying to ping as the next steps troubleshoot)
but since the Gateway is on two routers, you need their IP Addresses..
2.1 and 2.2 should be the IP addresses, since the MAC Address is except one Value the same (see above)
If you check Step 2, it also list the IPs that you should ping..
hope that helps.