Ramping up my reviewing.
Happily playing games for many, many years.
The developer of the game says yes.(http://talk.consimworld.com/WebX/.1dd8380d/370)
So, if as a result of Shock combat a Phalanx unit is TQ-1 cohesion hits, it first checks to see if it routs (if it doesn't, remove a cohesion hit).
If it would rout, 8.18 is followed in its entirity, allowing it to possibly not rout and end up on TQ-1 hits!
Note that if a Phalanx unit reaches its TQ in cohesion hits from missile fire, it just routs per 10.21 - it doesn't use this process.