You are using the wrong definition of ‘theory’ as it pertains to science. Here are two better definitions:
According to the National Academies of Sciences, a theory is “a comprehensive explanation of an important feature of nature supported by facts gathered over time. Theories also allow scientists to make predictions about as yet unobserved phenomena".
The American Association for the Advancement of Science defines a theory as “a well-substantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment. Such fact-supported theories are not "guesses" but reliable accounts of the real world."
As you can see, there are no guesses in a scientific theory.
Another question - how do you want god to be included in science?
Respectfully I disagree. Scientist, and you may fully believe the definition you put forth is the definition that applies to science but the one I used, and fully believe it to be, is what I meant it to be. There is no way, regardless of how many "Scientific Facts" that are provided for Science or anyone to absolutely know that which is impossible to know dogmatically.
As for your additional question, my answer is I don't want G_d to be included in Science for I submit that G_d or anything connected with the Spiritual realm cannot be tested, sampled, or analyzed by Scientific methods but Spiritual Issues rest entirely in the realm of faith something that Science denies is valid even though people exercise faith every day in some measure.
Hebrews 11:1-3 (CSBBible)
1 Now faith is the reality of what is hoped for, the proof of what is not seen.
2 For by it our ancestors won God's approval.
3 By faith, we understand that the universe was created by the word of God so that what is seen was made from things that are not visible.
The funny thing is Science still doesn't know beans about our own planet or exactly what's in the Core or even has answered all the questions about what lies under the oceans yet they are so confident in how everything became what it is and how everything began. Science cannot answer with any assurance exactly how large the universe is or if it ends and where if it does nor can any scientist comprehend the concept of eternity, with regards to time whether it's eternity past or eternity future. Christians do not require answers to all questions for Christians understand that there are things beyond human understanding or comprehension, things which are none the less accepted by Faith alone.
Science deals with the Physical Realm and cannot accept or envision a Spiritual Realm yet Black Holes, Dark Matter and other things within the Physical Realm is accepted until proved otherwise. Theories such as Parallel Universes and the like make them feel warm and fuzzy and feel that they have a handle on the things which they cannot know or answer.
The scriptures haven't changed since they were written yet they apply the same today as they did then.
1 Corinthians 1:18-31 (CEV)
18 The message about the cross doesn't make any sense to lost people. But for those of us who are being saved, it is God's power at work.
19 As God says in the Scriptures, "I will destroy the wisdomof all who claim to be wise.I will confuse thosewho think they know so much."
20 What happened to those wise people? What happened to those experts in the Scriptures? What happened to the ones who think they have all the answers? Didn't God show that the wisdom of this world is foolish?
21 God was wise and decided not to let the people of this world use their wisdom to learn about him. Instead, God chose to save only those who believe the foolish message we preach.
22 Jews ask for miracles, and Greeks want something that sounds wise.
23 But we preach that Christ was nailed to a cross. Most Jews have problems with this, and most Gentiles think it is foolish.
24 Our message is God's power and wisdom for the Jews and the Greeks that he has chosen.
25 Even when God is foolish, he is wiser than everyone else, and even when God is weak, he is stronger than everyone else.
26 My dear friends, remember what you were when God chose you. The people of this world didn't think that many of you were wise. Only a few of you were in places of power, and not many of you came from important families.
27 But God chose the foolish things of this world to put the wise to shame. He chose the weak things of this world to put the powerful to shame.
28 What the world thinks is worthless, useless, and nothing at all is what God has used to destroy what the world considers important.
29 God did all this to keep anyone from bragging to him.
30 You are God's children. He sent Christ Jesus to save us and to make us wise, acceptable, and holy.
31 So if you want to brag, do what the Scriptures say and brag about the Lord.