you need to seek the advice of an experienced attorney. I would ot accept the first offer from the prosecutor. An attorney should be able to get you a withhold of adjudication and prevent you from doing any jail time. You can always ask the judge for a withhold of adjudicatio, but most times when a judge sentences you to jail time, then there is a conviction, unless the jail is a condition of probation.
A witness statement should always be sworn and notarized if using it for the purpose of prefiling determination of a prosecutor deciding whether to file charges or not against a defendant. I typically have witnesses that are beneficial to the defense state under oath by a court reporter transcribing under oath verbally their testinmony.. I do this because it is more effective in potentially getting a case dismissed.
When a person is arrested they post a bond to satisfy the Court that they will return to all court hearings. At the conclusion of the case, whether by plea, or trial, the Clerk issues a Certificate of Discharge of Bond to the surety (the person that posted the bond) so that they may receive the monies back. Most jurisdictions usuallt deductthe amout of court costs and other fees owed before returnig the bond monies.