As you described, callbacks are for discrete changes in either state or parameters. Even VectorContinuousCallback is not applicable here, because the thing that’s continuous there is the mechanism for finding the right time to apply some change, not that change itself.
It looks like you can just make ω a LinearInterpolation from DataInterpolations.jl, which seems to have proper MTK integration: Using with Symbolics/ModelingToolkit · DataInterpolations.jl. It’s probably still a good idea to add the tstops.