That's one possibility, sure.
Remember how people used to speak of the 'aether'? Aether has waves and frequencies too. The charge aether puts on matter is of a different sort than ionization by electromagnetic energy.
What is a photon?
What is a wave?
What is energy?
What really is energy?
Is energy confined to 3 spatial dimensions?
Is there such a thing as time energy in the time dimension?
If there was, would it be carried by a certain kind of photon?
What does string theory hypothesize about the nature of space time?
How many dimensions are there really?
No limit?
The sun is an energetic source.
Is there any reason to believe the sun limits its energy emissions to the electromagnetic energy only?