According to your logs you are underboosting.
I went to the Cobb website and looked up max boost for an 04 WRX using the OTS stage 2 map. Depending on what map you are using the max boost is:
ACN91: 16.0 peak, 12.0 @ redline
91: 16.5 peak, 12.0 @ redline
93: 17.0 peak, 12.0 @ redline
Your target boost is 17.79 peak and ~15 @ redline.
Are you sure you are running an OTS map?
Your actual boost is right in line with what the Cobb map notes say it should be for a stage 2 map. But your WDC is maxed out trying to hit 17.8 target boost.
You did have what initially looks like a small boost spike in 3rd gear pull 3. This is more than likely due to your target boost values and not really a boost spike. Hitting 18.1 with a target of 17.8 is just fine.
The question is why are your target boost values so high for an OTS map?