Well.....I'm certainly no expert in this area....but what about these statements?
Origen (Eusebius, H.E. 6.25.4)
"As having learnt by tradition concerning the four Gospels, which alone are unquestionable in the Assembly of God under heaven, that first was written according to Matthew, who was once a tax collector but afterwards an apostle of Jesus Christ, who published it for those who from Judaism came to believe, composed as it was in the Hebrew language."
Eusebius, (H.E. 3.24.6)
Matthew had first preached to Hebrews, and when he was on the point of going to others he transmitted in writing in his native language the Gospel according to himself, and thus supplied by writing the lack of his own presence to those from whom he was sent."
Epiphanius (ca. 315-403)
Bishop of Salamis, refers to a gospel used by the Ebionites (Panarion 30. 13.1-30.22.4). He says it is Matthew, called "According to the Hebrews" by them, but says it is corrupt and mutilated. He says Matthew issued his Gospel in Hebrew letters. He quotes from this Ebionite Gospel seven times. These quotations appear to come not from Matthew but from some harmonised account of the canonical Gospels.
Jerome
Also asserts that Matthew wrote in the Hebrew language (Epist. 20.5), and he refers to a Hebrew Matthew and a Gospel of the Hebrews-unclear if they are the same. He also quotes from the Gospel used by the Nazoreans and the Ebionites, which he says he has recently translated from Hebrew to Greek (in Matth. 12.13). We have quotations from such a source from Cyril of Jerusalem, Jerome, Origen, Didymus, Clement of Alexandria.
“...mistranslated Hebrew coloquialisms, and puns”.
Is that what you are suggesting? That Matt. couldn't properly translate his own text?