Perhaps I am misunderstanding, but is that a new rule? I ask because myself and four other peers that I know of were selected for Intel DCO this January, all
without 5 years of intel experience. 2 came from finance (as the OP would be doing), 2 from law, and 1 from tech. All were within 2-4 years of graduating undergrad.
While I understand why intel experience is desirable, it's clear from the endorsements received (many from folks with distinguished service in military intelligence communities) that there are other experiences which lend themselves to useful preparation on both the leadership and analysis fronts.
If this link is accurate, intelligence experience is "strongly desired" but not required. I also don't see anything alluding to a requisite 5 years, and the above mentioned anecdotes indicate that different experiences, while perhaps uncommon, are also not disqualifiers. The fact that we were all processed through different districts leads me to believe this wasn't simply a recruiting error
https://www.navycs.com/officer/intelligenceofficer.html
Again, not trying to be contrarian, but I think it's important that stated requirements are accurate.