Use of information in subpoenas

The opposing party "vacated" what exactly? To whom were the subpoenas issued? Your post suggests that the person/institution receiving the subpoena responded and provided the requested information. Is that correct? Did you ever file an objection to the subpoena with the court? And what is the underlying dispute between you and the opposing party? And what use of the information concerns you? Using it as evidence in court or something else? There are a lot of details needed here to answer the question. If you don't have an attorney you might want to consider at least consulting one or two for assistance. The other side has an attorney, and that puts you to a disadvantage in this fight if you don't also have one.

 

Terminology is always important.

The person filing for divorce is called the Petitioner.

The other spouse, who didn’t file for divorce, is called the Respondent.

Attorneys aren't engaged in combat, or sport.

If you're the respondent, you refer to the other party's attorney as, petitioner's counsel.

You're involved in litigation, not wrestling, boxing, or any other sport. Litigation isn't combat.

If you filed for divorce you are bringing a lawsuit against your spouse.

In criminal cases the people involved in litigation are called the plaintiff and defendant.

The plaintiff is a branch of government, as in county, township, municipality, state, or federal government.

In civil cases, however, such as dissolution of marriage cases, the people involved are called the petitioner and the respondent.

Someone involved in civil litigation is referred to as a litigant.

 

More about terminology.

The interval between filing for divorce and the trial is the Discovery period when the parties obtain information from each other. They do this by requesting production of the required information.

If you are one of the parties to the divorce you might have served a request for production and not a subpoena. The result is similar.

Getting back to your first question:

The answer is likely to be yes. If your spouse was entitled to the information in the first place then it can be used for trial or mediation.