I was curious about this so I did some research, you can use iptables for this. It's installed on the Indeni VM too. I tried this:
indeni@indeni-server:~$ sudo iptables -t nat -A OUTPUT -p tcp --destination 1.1.1.1 --dport 22 -j DNAT --to-destination 192.168.197.36:22
indeni@indeni-server:~$ ssh 1.1.1.1
The authenticity of host '1.1.1.1 (1.1.1.1)' can't be established.
RSA key fingerprint is c9:9d:a6:a0:0b:b6:d5:07:3c:d1:eb:92:c0:a7:13:97.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '1.1.1.1' (RSA) to the list of known hosts.
[email protected]'s password:
Last login: Wed Oct 4 17:19:47 2017 from 192.168.197.15
[Expert@lab-CP-GW1]# ifconfig eth0
eth0 Link encap:Ethernet HWaddr 00:50:56:90:EB:07
inet addr:192.168.197.36 Bcast:192.168.197.255 Mask:255.255.255.0
...
So in your case, you can add a line for each of the devices, alternating the destination IP (1.1.1.1 in my example above) and changing the port (the ":22" at the end). NOTE that some devices that Indeni connects to require more than just SSH - they may require HTTTPS/443 too.
Also, this can be a bit of a hassle when adding devices. You'll need to add a line in iptables, matching ports in the jump server and then add it in the UI. This is something you can script though :)