Could you clarify why this data cannot be read directly from the slave device?
Modbus TCP uses regular TCP/IP packets, which can be routed via the internet and should be accessible directly by the software that you are using to read this data.
Modbus TCP Master package on our devices can be used to periodically send the data to a remote server, or in the latest firmware versions, Modbus RTU can be converted to Modbus TCP to also be routable via the internet.
However, if you do need to get the values into the RUT955 first, then you are on the right path, and here is a configuration example of how it can be achieved. The issue seems to be incorrect data types, as the data you are writing to the regfile is of an unsigned float type, but the application seems to be reading it as an (unsigned?) integer.
If your device is supported, please update to the latest firmware version, which can be downloaded here, as the version you are currently using is no longer supported.