This KB explains if there is telemetry support for getting the wavelength information for optics on QFX5110

The telemetry feature to get wavelength of the optics in qfx5110 is not supported at this time.

Even the pathfinder does not show wavelength:

https://apps.juniper.net/ydm-explorer/select-software?software=Junos%20OS&release=24.4R1&moduleId=All&datamodel=OpenConfig&filter=Supported&platform=31705110