The wiki says:
I answered a call from Bohemia who was DoWed by Poland. Bohemia negotiated peace and I got the relations boost with HRE members but no IA. Is it because Poland isn't in HRE?
Winning a defensive call to arms will grant as much as 30 IA, in addition to a substantial relations boost with every HRE member nation. But it will only be awarded if the defensive War Leader negotiates a victory. The Emperor can negotiate a separate peace, but won't earn any IA.
I answered a call from Bohemia who was DoWed by Poland. Bohemia negotiated peace and I got the relations boost with HRE members but no IA. Is it because Poland isn't in HRE?