Follow the Anaren delay line datasheet and use pins 1 and 4.
Originally, when the reference design was created, there were only 2 pins and pin 4 used to be named pin 2.
SC2200
Recommended for New Designs
The SC2200 belongs to the 4th-generation family of RF PA linearizers (RFPAL) that provides increased integration and functionality over the previous generations...
Datasheet
SC2200 on Analog.com