How to format C# DateTimeOffset exactly same as in SQL Server's DateTime2(7) format?

Question

Saving following two DateTime values in SQL Server's DateTime2(7) column results in same DateTime2 value.

var dt1 = new DateTimeOffset(638124107765100000, TimeSpan.Zero);
var dt2 = new DateTimeOffset(638124107765000000, TimeSpan.Zero);

Value in Sql Server's DateTime2(7) column.

2023-02-19 13:39:36.5066667

This value goes through Entity Framework. Now I can see that SQL Server uses some different form of storage to store value, so the value gets changed when we read it back.

Now I have no problem with little lost precision but I want to format DateTime in such a way that the text should match exactly what is stored in SQL Server.

The only way currently I can do is by ignoring whole milliseconds above 10.

I have tried the following:

private static DateTimeOffset ToSqlServerPrecision(DateTimeOffset dt) {
    var n = Math.Round((double)dt.ToUnixTimeMilliseconds() / (double)1000, 1);
    n = n * 1000;
    return DateTimeOffset.FromUnixTimeMilliseconds((long)n);
}

ToSqlServerPrecision(dt1).ToString("yyyy-MM-dd HH:mm:ss.fffff")

Both result in:

2023-02-19 13:39:36.50000
2023-02-19 13:39:36.50000

But I doubt, this will might fix all edge cases.

I have also tried following,

private static DateTimeOffset ToSqlServerPrecision(DateTimeOffset dt) {
    var p = (double)1/3; // or 3.33 
    var n = Math.Round((double)dt.UtcTicks / p, 1);
    n = n * p;
    return new DateTimeOffset((long)n, TimeSpan.Zero);
}

Both result in:

2023-02-19 13:39:36.51000
2023-02-19 13:39:36.49999

I guess Ticks to SQL Server compatible time storage isn't simply casting milliseconds/ticks to double conversion.

All I want is to get exact same text representation that is stored in SQL Server.