Agree with post above. Likewise not a DODMERB expert - however, I think the key here is were there any diagnoses documented / assigned to you during your 99 day hospitalization, any surgeries performed that could cause concern / or, any conditions DXd or medications administered that might require additional medical information or could be concerning/ might need a waiver. You'll have a massive medical record from 99 days in the NICU but your pediatrician/ chart might clearly document that there are no concerns, affirm there were no disqualifying procedures, diagnoses or medications.
On just a kind note, your distance running and history make you a great candidate - seems to me, you are a fighter to have gone through that rough start so I'm rooting for you to stand shoulder to shoulder with my DS and other active military soon - just the type of scrappiness/ grit/resolve I've found in 20 years of volunteering with the military and growing up with a military household makes a great military leader.
Example of a diagnosis / damaging impact that could cause concern potentially: Premature atrial or ventricular contractions that required treatment then resulted in impairment.