Was Thaddeus Judas Iscariot?
Judas Iscariot, not to be confused with St. Jude Thaddeus, was one of Jesus' twelve Apostles. Judas Iscariot is also not the same as Jude Thomas (known to us as St. Thomas the Apostle).
St. Jude, also called Judas, Thaddaeus, or Lebbaeus, (flourished 1st century ce; Western feast day October 28, Eastern feast days June 19 and August 21), one of the original Twelve Apostles of Jesus. He is the reputed author of the canonical Letter of Jude that warns against the licentious and blasphemous heretics.
Judas Iscariot, (died c. 30ce), Disciple who betrayed Jesus. Judas was one of the original Twelve Apostles. He made a deal with the Jewish authorities to betray Jesus into their custody: in return for 30 pieces of silver, Judas brought an armed guard to the Garden of Gethsemane and identified Jesus with a kiss.
He was said Judas James, for he was brother to James the Less, and he was called Thaddeus, which is as much to say as taking a prince; or Thadee is said of Thadea, that is a vesture, and of Deus, that is God, for he was vesture royal of God by ornament of virtues, by which he took Christ the prince.
St. Jude Thaddaeus was one of the Twelve Apostles of Jesus Christ. He lived in the 1st Century, and witnessed first hand, our Lord's ministry. He was present at the Last Supper according to Scriptures.
Catholics and Eastern Orthodox Christians believe this Jude is the same person as Jude the Apostle and that Jude was perhaps a cousin, but not literally a brother of Jesus, or perhaps St. Joseph's son from a previous marriage.
Thaddeus, alternatively called Thaddaeus and also known as Judas and Lebbaeus, was a former stonemason in Bethsaida and became one of the twelve disciples of Jesus.
We also know that Thaddeus, like other disciples, preached the gospel in the years following the death of Jesus. Tradition holds that he preached in Judea, Samaria, Idumaea, Syria, Mesopotamia, and Libya, possibly alongside Simon the Zealot.
Accomplishments of Thaddeus
Thaddeus learned the gospel directly from Jesus and loyally served Christ despite hardship and persecution. He preached as a missionary following Jesus' resurrection. He may have penned the book of Jude.
Judas Iscariot (/ˈdʒuːdəs ɪˈskæriət/; Biblical Greek: Ἰούδας Ἰσκαριώτης; Classical Syriac: ܝܗܘܕܐ ܣܟܪܝܘܛܐ; died c. 30 – c. 33 AD) was a disciple and one of the original Twelve Apostles of Jesus Christ.
What does Iscariot mean in Hebrew?
a person who betrays a friend; traitor. 3. a brother or relative of James and also of Jesus (Matthew 13:55).
Matthew's Gospel is unique in mentioning the 30 pieces of silver as the price Judas was paid for the betrayal (see 26:15). It also is the only account that tells of how Judas later regretted his actions, threw the money back at the chief priests and hanged himself (27:3-5).

Biblical Names Meaning:
In Biblical Names the meaning of the name Thaddeus is: That praises or confesses.
a male given name: from an Aramaic word meaning “ praise”
Judas Iscariot was one of the Twelve Apostles. He is notorious for betraying Jesus by disclosing Jesus' whereabouts for 30 pieces of silver. Judas brought men to arrest Jesus and identified him with a kiss. Jesus was then arrested, tried, and executed.
Judas, the apostle said to have betrayed Jesus, was the 13th guest to the Last Supper. (See "Lost Gospel Revealed; Says Jesus Asked Judas to Betray Him.") As for Friday, it's well known among Christians as the day Jesus was crucified.
Intriguingly, Judas Iscariot is the only one of the apostles whom the Bible (potentially) identifies by his town of origin. Some scholars have linked his surname “Iscariot,” to Queriot (or Kerioth), a town located south of Jerusalem in Judea.
The brothers of Jesus or the adelphoi (Greek: ἀδελφοί, translit. adelphoí, lit. "of the same womb") are named in the New Testament as James, Joses (a form of Joseph), Simon, and Jude, and unnamed sisters are mentioned in Mark and Matthew.
The Chosen (TV Series 2017– ) - Giavani Cairo as Thaddeus - IMDb.
The inhabitants of Judah were the Judahites (later abbreviated as “Jews”), and thus Judas' name is equated with the Jews.
Does Judas go to heaven?
It is one step, but looking to Jesus as the crucified, risen Savior for one's soul is what brings salvation, assurance of being in heaven for eternity. So from what Jesus said in Matthew 26:24, it would certainly appear that Judas is not in heaven.
He died a martyr's death — as tradition tells us, he was clubbed to death and his head was then shattered with a broad ax. Sometime after his death, Jude's body was brought to Rome and placed in a crypt in Saint Peter's Basilica.
"The Son of Man goes, even as it is written of him, but woe to that man through whom the Son of Man is betrayed! It would be better for that man if he had not been born." Judas, who betrayed him, answered: "It isn't me, is it, Rabbi?" He said to him: "You said it."
In Matthew, Judas is depicted as a traitor of a Davidic king and a failure as a disciple. In Acts, the portrait of Judas presents him as an apostate apostle and a defeated enemy of God's people. In Papias, Judas is characterized as a greedy and intemperate miscreant who plots against a righteous benefactor.
His original name, Judas, was changed to Jude by early writers who translated the New Testament to distinguish him from Judas Iscariot. Evangelists Matthew and Mark preferred to call him Thaddeus, which means courageous in Aramaic.