The Kiddushin was a good Kiddushin but it is a good idea to mention it to the Rav to check because it is better to make a second Maaseh Kiddushin.
Explanation:
The Gemara Kiddushin 52a: Rav and R’ Yochanan are of the opinion that one who marries a woman with a stolen object she is not married. 52b: There was a woman who was washing her legs in a basin of water, a man passed by and grabbed money from his friend and threw it at her and said Harei At… The man came before Rava and asked him if he was really married. Rava answered him we should be worried for R’ Shimon who said that Gezeila (grabbing money) generally the one he stole from giving up hope of getting it back (and therefore it becomes the robber’s and he might be married).
We see from here if there was Yeush-the person gives up hope of ever getting it back- the thief owns the money and can use it for Kiddushin. Also, when the thief gives the ring over there is a ‘change of hands’ which means that the receiver actually owns the object (if he is caught then the receiver would have to pay the owner but he does not have to give it back.)
So rules the Shulchan Aruch (EH 28:1): One who marries a woman using as a stolen object if the owners gave up, and he knows about it then the object is his and she sim arid otherwise not.
This even applies by Genzel from a Non-Jew. There is an argument about whether stealing from a Non-Jew is from the Torah(Rambam Geneiva perek 1, Semag and Tur CM 348) or is it just Rabbinical prohibition (Rashi in Sanhedrin 57 and Tosfot Baba Kama 113). However, everyone agrees that we must return to the Non-Jew either bee of Kiddush Hashem, or because of Dina DeMalchuta Dina.
The Rema in EH 28 writes: If he married her with goods stolen from Goyim she is Mekudeshet since he only had to return because of Kiddush Hashem.
So rules the Bet Shmuel but the Chelkat Mechokek argues since there is an opinion that it is from the Torah then it is not his and if the marriage doesn’t no work. So rules the Gr”a.
According to may opinions there is no difference whether he stole from a Jew or he stole from a Non- Jew.
Therefore, if you know the Non-Jew gave up hope of ever finding it then it is considered Yeush and when he gives the ring it changes hands and therefore it is hers completely.
However, he must know that they have given up hope since the Shulchan Aruch in CM 368 writes that since the Secular laws punish a thief based on circumstantial evidence then one does not lose hope so easily. This is as opposed to Jewish law which requires actual proof (like witnesses) that this object was stolen so it is much harder to get back and he gives up. So, here if he has a file by the police there might be Yeush.
Also, you have to know he gave up hope before the Chatunah because the Noda Beyehuda writes that the witnesses don’t know there was Yeush and maybe the there was no Eidem at all.
There is one other possibility that the Chatan married her not by Kiddushin but Chuppah. The Gemara in Kiddushin write s 5a: Rav Huna said that (being under) the Chuppah works to make them married. Rava argued.
Most Poskim rule like Rava however Rabbeinu Chananel rules like Rav Huna in as much that she would need a Get from him to separate. So rules the Shulchan Aruch 26:2 She is no married but some say she possibly married. Some say that he needs to actually say “Harei At Mekdueshet B’Chuppah. R’ Akiva Eiger says you don’t have to.
So, she is possibly married, at least she would need a Get to separate.
Therefore, you should say something to the Rav to check into it.
