B1/B2 Visa for cousin

Hi!

My mom’s cousin and his wife have always wanted to visit the US. They’re both in their 40s. These are their profiles:

Country: India

Cousin: owns a business that’s subsidized by the government. Has multiple rental properties

Cousin’s wife: law clerk at the district court

Questions:

1. They filed their DS160s separate. They got appointments for the same day. Do they attend their interviews together or at separate counters?

2. they both mistakenly put their planned length of stay as 5 months, but it’s really only 3 weeks. Should they mention that they made a mistake during the interview? If the officer asks for length of stay and they say 3 weeks, wouldn’t it seem like a discrepancy between their answer and what’s on the DS160 form?

3. they’re most likely going to stay with me and my husband if they do get the visa. My husband and I are both a US citizens by birth. Do they need any of our information like our passport copy/tax return etc for the interview?

4. they’re just coming for tourism, not for a particular event like a wedding/graduation. Would it be ok to just say they’re coming for tourism or is that too vague of a response? what are their chances of approval? 😁

Thank you so much!!