Being ghosted by company after written offer? Rescinded?

So after about 4 months of searching and countless applications, interviews, and rejections, I finally received a verbal job offer yesterday. This sub has taught me to be suspicious until you get it in writing, but the written offer just came in today. However, this next part is what's making me nervous. I emailed both the hiring manager and HR a list of some questions regarding the position and have gotten no response. The questions weren't about salary, more like policy, vacation days, detailed health benefits, etc. Could they be ghosting me because they're planning on rescinding my offer?

Sorry if it sounds ridiculous, just paranoid now after so many broken promises from recruiters.

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