Sucks that companies won't share schematics. Doesn't surprise me with Sanken though. I messaged them about their super short 4" shotgun mic, asking about how it handles interiors, because if it has an interference tube there's always the chance of comb filtering, and what I got back was a message about how the side rejection is much better than other mics, without addressing my actual question, and telling me if the room is too noisy I should be using one of their longer shotgun mics, which will be even less ideal in an indoor reverberant space. Not really on topic, but that pretty much turned me off buying any of their mics. Deity also gave me a similar reply about how their S-Mic 2S tube is short enough that it shouldn't cause issues even though they acknowledge it will in a video on their YouTube channel, but they didn't tell me their mic is superior, and that's a $300 mic vs like $900 or whatever the Sanken costs.
Definitely not what I would call good customer service (from either, but at least Deity shows theirs is still vulnerable to comb filtering/phase issues), because it tells me that their sales reps either don't know their stuff, or care more about one sale than a repeated relationship and actually informing and helping the consumer.