Before I start, I advice those who have not gotten to this part to not read this post as it'll obviously contain spoilers.
Anyway, I've made an account to ask about this beyond exhausted topic (apparently everyone gets stuck at this point, and I'm no better.)
The darned last remaining officer! I found all the living 4 ones and was able to locate the room which the Growlithe resided in at the healing guy's place. I'm also fully aware of the secret passage which leads to the said location of the Pokémon. As far as I'm aware, everything should be fine, but I'm unable to access the secret passage? All I know is that it's entrance is situated on the side of the building where the healer was, I'm unsure if I've done something or skipped a step by accident. I literally read up on every post I could find regarding this topic and even watched walkthroughs.
TL;DR: I know about the secret passage but it seems inaccessible despite the Growlithe still being there.
I apologize if the answer to this issue is an obvious one, I just feel stumped and would really appreciate some guidance. Thank you.
