Prosecution for Murder and Engaging ordered by a Mexican Drug Cartel. Strongest evidence linking defendants to the crime are phone tolls. State filed business records affidavit but not within the 20 day period. Because we did not file within the 20 days do we need a custodian or records to satisfy the rule? Does the judge have the ultimate discretion? Any help would be appreciated. Trial starts on Monday

You need a custodian of records, absolutely, to sponsor the records. No discretion on this one.

If you did not file the records as required, I would bring the issue up in pre-trial and tell the judge that due to your error, you did not file the records in a timely fashion and that you will not object to a continuance if the defense is claiming surprise. I think that looks better on the record for the appeal.

If defense attorney says he does not want continuance but then screams like a banshee with his toe cut off that it is trial by ambush and surprise at the time you seek to admit the records, it would be nice to have that pretrial offer of continuance on the record for your appellate attorney to argue with.

If it were me in that boat, I'd be beggin' the boss (and apologizing profusely for my error) for funds to fly your custodian in if that is what needs to happen.

And it is not 20 days, but 14 days. Here's some excerpts of the rule:

(10) Business Records Accompanied by Affidavit.

...that such record or records long with such affidavit are filed with the clerk of the court for inclusion with the papers in the cause in which the record or records are sought to be used as evidence at least fourteen days prior to the day upon which trial of said cause commences, and provided the other parties to said cause are given prompt notice by the party filing same of the filing of such record or records and affidavit, which notice shall identify the name and employer, if any, of the person making the affidavit and such records shall be made available to the counsel for other parties to the action or litigation for inspection and copying. Notice shall be deemed to have been promptly given if it is served in the manner contemplated by Rule of Civil Procedure 21a fourteen days prior to commencement of trial in said cause.