If the router can work in “AP mode”, then yes. Set it to AP mode, give it an SSID to broadcast under, and it will serve as a wireless access point to the subnet controlled by the router that handles that subnet.
I am thinking that maybe the OP’s network does not have proper bi-directional routes established. As such, the MyCloud gets requests, but cannot send responses.
See for instance, this hypothetical scenario:
NetA = 192.168.0.XX
NetB = 192.168.1.XX
NetC = (public internet)
NetA sits between NetB and NetC, like this:
NetC <–> NetA <–> NetB
The MyCloud is attached to NetA.
The OP’s workstation is attached to NetB.
A request is sent from the OP’s workstation, and goes out the default gateway on NetB, which routes the traffic to NetA. However, NetA does not have a defined route to respond back to the device on NetB, and tries to use the default gateway, which points to NetC, which is the portal to the internet.
EG, NetA would need rules like this:
192.168.1.0 255.255.255.0 → 192.168.0.254 (<–route back to NetB–Suspect missing!)
... 255.255.255.0 → 192.168.0.1 (<–Route to internet)
and NetB would have rules like this:
... 255.255.255.0 → 192.168.1.1 (<–Route to NetA)
All requests not in NetB will be forwarded to NetA, where any request not serviceable by NetA, will be forwarded to NetC (internet). Without the return route from NetA to NetB, The devices on NetB will be unable to get responses from the devices on NetA.
Programming routers is not the purpose of this community board though.