Why should the poster not make restitution for stolen items? It is immaterial if the company was harmed or not. The priest can only give absolution for remorse for stealing. The poster has committed grand theft; $10,000 is a LOT of stealing. The absolution should be contingent on repayment, even if it takes years. The person can still be in good graces by continuing the payments and being remorseful. If the priest says no payback is necessary then he is wrong. He can only give absolution for the sins against God’s laws. That does not affect personal responsibility to the wronged.
Maybe yes, maybe no.
Your use of the word “stolen” may be the point. If there is software out there (something beyond, say, Microsoft Powerpoint) that an individual “pirates”, the questions are perhaps a bit finer than you are reading.
If they did it simply out of curiosity, made no use of it professionally, did not use it in commerce, but simply looked through the program an then deleted it, how has the software company been harmed? Odds are the company has no means of providing someone the opportunity to review the software; they are only set up to sell the software to commercial users. But if the OP is not a commercial user, and does not use the software commercially, the company has not lost a sale (because they only sell to commercial users). All that has occurred is that someone looked at the software.
Software companies don’t want people pirating their software and then using it for its intended purpose; that is why they sell it.
Let’s take another turn - music and videos. Music and videos are produced for individual consumption; it used to be done in the form of records, then tapes, and now it is done through software. One may be able to pirate the video and watch it - and a company on the other end is out a $5 to maybe $15 sale. It is easy to do that repeatedly, to the point of thousands of dollars, but the individual item is what one is judged on, an moral law while restricting such behavior does not normally judge that as serious a matter as pirating a much more expensive item.
The $10,000 has your attention, and that has to do with civilian criminal law, not moral law. The two are not identical; similar, but not identical.
Let’s assume, for the moment, that the OP pirated software for personal use (we can go back to Microsoft). What is the difference between that, and going over to a friend’s house and using their copy, or to school and using the school’s copy? The other two have been paid for; his not; arguably the friend’s use is more problematic than the school’s (as that is intended for at least semi-public use). In all three cases, however, that piece of software is fast approaching de minimus if not dead square in it, considering the amount of money Microsoft makes each year on the sales. That is not to say it is not morally wrong; but the moral wrong does not appear to reach the level of a serious wrong.
None of this is to suggest that the OP should not address the issue with a priest, but neither is it assured that he will have to pay something in the range of $10,000 to anyone. What he did with the software is an element going both the moral guilt (degree) and to restitution if any.