Resonance frequency of a system
You cannot determine from measurements at just one port of the circuit what the internal structure of the circuit resonances are....that is, what the current pattern is within the circuit. If you can identify a resonance from the behavior at one port with a frequency sweep, you could measure or simulate the currents or voltages in the components within the circuit when driven at that frequency to determine which components are 'participating' in that resonance. By 'participating' I mean that for the particular resonance, the component has current running through it.
If a component has no current through it when the circuit is driven at a resonant frequency, then that component is not participating in that particular resonance. A resonance could involve just a subset of the components, and so a resonant frequency could be completely insensitive to the values of some of the components in the circuit (the non-participating ones).
There is another way to analyze resonant circuits like this with an ac mesh analysis, which involves finding eigenfrequencies of a set of matrix equations, but this is a rather different set of tools than what you are using.