How to connect muRata XRCGB_F_M Series (XRCGB27M120F3M00R0) to microprocessor oscillator
This package is quite small for Hand Soldering and will have issues of accuracy but you can definitely clock-up CPU.

You can use CRO probe in 10X mode so that probe capacitance will be reduced and that can be used for checking oscillations.  It might load crystal but will not stop it to oscillate.  You may see imperfect sine wave or reduced amplitude which will be OK for initial verification i guess.

You can ground Pin 2 and 4 as they are like shield.  Check whether those pins are shorted with body.  If yes then connecting to Ground will reduce noise and external interference.