They sould both be good for life. You would only need the titers if you did not have any records (proof) that you had them. Then, you could get a titer instead of getting new shots.
The waiver for the meningities is on the same form as all the vaccines. You just sign below section A which states:
I have read the information provided on the instruction sheet and I decline receipt of vaccine for Meningococcal Meningitis.
There is also a line for Hepatitis B which can be waived for students who are NOT going into a health related field. So, we MUST get the Hep B.
By the way, you would be a fool to take my word for it about the MMR and Hep B being good for life. To confirm, call the UF Student Health Care Center at (352) 392-1161. Best to get that information from the source since you have so much riding on it.
But, if my opinion means anything to you, then the MMR and Hep B are both good for life...however, you may see some diminished protection over time...so to protect yourself more, you could get new shots...but as far as UFCOP or any other official requirements go, you are good for life.