He; like Nature; abhors a vacuum.
There MUST be a 'theory' for EVERYTHING; even if that means 4-5 of them do not quite fill the bill and conflict with each other.
Job 38 New International Version (NIV)
1 Then the Lord spoke to Job out of the storm. He said:
2 “Who is this that obscures my plans
with words without knowledge?
3 Brace yourself like a man;
I will question you,
and you shall answer me.
4 “Where were you when I laid the earth’s foundation?
Tell me, if you understand.
5 Who marked off its dimensions? Surely you know!
Who stretched a measuring line across it?
6 On what were its footings set,
or who laid its cornerstone—
7 while the morning stars sang together
and all the angels[a] shouted for joy?
31 “Can you bind the chains[b] of the Pleiades?
Can you loosen Orion’s belt?
32 Can you bring forth the constellations in their seasons[c]
or lead out the Bear[d] with its cubs?
33 Do you know the laws of the heavens?
Can you set up God’s[e] dominion over the earth?
Yes, there tends to be competing theories for most things that we don;t understand well enough. People keep investigating, building up knowledge until an answer becomes clearer. If new information or knowledge comes to light in the future that contradicts the original understanding, the theory gets changed.
That’s why we have antibiotics, cancer treatments, spacecraft orbiting distant planets etc. It’s one of the best things about humanity.