Triton FetHead Phantom with a Neumann TLM 103: the one inline booster a condenser survives
Yes. With the FetHead Phantom already in line, the Scarlett 2i2 4th Gen only has to supply about 15 dB of the 69 it publishes. Those are the published figures.
The hard gain is already done. The Triton Audio FetHead Phantom sits in front of the Focusrite Scarlett 2i2 4th Gen, so the interface preamp is no longer the thing that has to rescue a quiet microphone.
Neumann rates the TLM 103 at -32.5 dBV/Pa, the voltage from a loud 94 dB tone at the grille. A speaking voice is closer to 85 dB, so the preamp still has to find about 15 dB to land near −9 dBV. That −9 dBV figure is just a tracking level: high enough to use, with space before the converter clips.
Feed the interface from the booster's output and do not stack a second microphone preamp on top. Most inline boosters spend the 48 V themselves. That is fine for a dynamic. If this microphone is a condenser, read the booster's manual before you leave it in the chain: if it does not pass phantom, the capsule goes silent.