I've got an offer for internship at a very reputed company. But they were unable to find out the gaps I had in my academics as I dropped out from college for 3-4 years in spite of getting good grades. The reason was I was involved in some organisational work which interested me more. But later came back and completed my degree again with good grades. So before joining should I take initiative to explain them about the gaps even though they have not found? (Actually anyone can make out that there's a huge gap but they couldn't find.)
Assuming you didn't outright lie on your CV, I don't see any reason why it matters whether you paused college at some point and finished it later. Assuming your resume reads something like "graduated 2015, worked at organization 2012-2014", they could have asked you what you did before 2012 but decided not to, it isn't your responsibility to guess whether or not it didn't occur to them or if they just didn't care.