We do not have any original autographs of the letters of Ignatius. The Greek copies we have date from about the 3rd or 4th century; some claim as late as the 6th century. Many of the extant copies have two different versions of many of the letters. Most scholars reject the longer versions as being forgeries; some reject the shorter versions, and some reject a cross between them. Some scholars reject all of the extant copies of Ignatius' writings as being forgeries, or at least as being alterations of what Ignatius originally wrote.
Ignatius, however, was not a Hebrew, and it is highly doubtful that he actually understood the Hebraic usage of the words for "God/god".
The claim that he was a student of the apostle John does not mean that his writings reflect what John believed, anymore than the writings of Joseph Rutherford can be used to reflect what Charles Taze Russell believed.
I do not have the letters attributed to Ignatius in the Greek, nor in the Latin. I am left to mostly depend on somebody's translation of those letters into English. From the translations, I cannot tell in the letters to the Ephesians, Traillians, the Smyrneans, Polycarp and the Romans if Ignatius is attributed to referring to Jesus in the sense being "our Supreme Being," or, in accordance with Hebraic general usage, as "our might / our strength", similar to such Hebraic usage as found in Genesis 31:29; Deuteronomy 28:32; Exodus 7:1; Nehemiah 5:5; Psalms 36:6; 82:1,6; Proverbs 3:27; John 10:34-36. I assume that the extant short copies do refer to Jesus in the sense of "our Supreme Being". Nevertheless, it is possible that Ignatius originally referred to the Father as "our God", as did Paul (Galatians 1:4; Philippians 4:20; 1 Thessalonians 1:3; 3:9,11,12), and that later copyists copied it as being applied to Jesus rather than the Father. Otherwise, being of Gentile descent rather than Hebrew descent, Ignatius, not being Hebrew, and due to the apostasy that had already begun in the first century, may himself not have been aware of the Hebraic usage of the words for "God/god" and thus may have actually misunderstood John 20:28 as referring to Jesus in sense of "my Supreme Being."
Epistle to the Ephesians
Introduction to Ignatius of Antioch
Regardless, in none of the letters attributed to Ignatius have I found any mention of the idea that the God of Abraham, Isaac and Jacob is more than one person.
Additionally, are we to assume that any of the letters attributed to Ignatius rellect what John or the apostels believed in every detail?