OK, I have read the verses you placed
Good. A place to begin.
And this is what make's your Denomination
We, who are members of the Seventh-day Adventist
movement (though having a name (thus 'denominated' (of name) in that sense only), inspired of by God) are not a 'denomination' with a creed, but rather we are a prophetic movement with a special mission prophesied in scripture. Any person simply taking the name 'Seventh-day Adventist' does not necessarily make them one or true. There are many 'Babylonians' in 'Jerusalem' (who will go out from us in several ways, some of whom already have), and many of 'Israel' (Jesus) in 'Babylon' at the moment (which will come out and join us in the time to come; Revelation 18:1-5, the repetition of Revelation 14:8). There is a state of flux presently.
Not "a remnant". "The" remnant. It is identified with specific criteria in scripture, only a few scriptures were given, and there is many more. There is only one such body (Seventh-day Adventist movement, made up of all peoples, from all faiths (having come out of those false systems, into the body which keeps the commandments of God and has the faith of Jesus Christ and the testimony of Jesus Christ, which is the spirit of prophecy (Revelation 19:10)), though with many members, and much of whom are presently in many other 'faiths' (Harlot daughters and Mother of Revelation 17, systems of theology) at the moment. There is Elijah, and 7,000 that haven't bowed the knee to Baal, and many 'Samaritans' (like the woman at the well) about to join with us.
So could there be any other souls out there that might also be a remnant
"a remnant", no. Part of "the" remnant, yes. Many are still in darkness, though serve God with what they know in the light that they have, and are ignorant yet still of their high calling, but when the light comes to them, they will come to it.
outside of your denomination?
Most of "the" members of the remnant is presently in 'Babylon' and her daughters. The call is even now swelling, and those loyal to Christ, will come out, and join the one body.
Revelation 14:12 - Here is the Patience of the Saint's,Here are those that Keep the Commandments of God and the Faith of Jesus Christ!
There is only one such body.
I almost always have a problem when a group kinda states that they are the only one's!
There is only one true body, one truth (and every group claims it, but only one group meets the criteria in scripture):
Ephesians 4:4 There is one body, and one Spirit, even as ye are called in one hope of your calling;
Ephesians 4:5 One Lord, one faith, one baptism,
Ephesians 4:6 One God and Father of all, who is above all, and through all, and in you all.
Relativism is of the devil.
I am not saying you have declared this, so don't get me wrong!
I do not expect you to believe me based upon a single post. I expect you to test according to the criteria set by scripture.
So is there any others out there that could be as you believe, a remnant?
"a remnant", no. Part of "the" remnant, yes, though the majority do not understand their high calling yet and many have erroneous beliefs (which they will have to give up).