Bear with me, this might well be wrong and way out to lunch, but here goes.
My theory is that at the end of "Into the Forest I Go", Lorca jumped the Discovery to where the Buran was destroyed, in an alternate universe.
That debris field? The remnants of the Buran.
How Lorca escaped the Buran? He somehow crossed into a different reality.
When he says "let's go home?" He means HIS home, his universe.
Now the question is which universe is the Prime Universe we're all used to seeing? That remains to be seen.
My theory is that at the end of "Into the Forest I Go", Lorca jumped the Discovery to where the Buran was destroyed, in an alternate universe.
That debris field? The remnants of the Buran.
How Lorca escaped the Buran? He somehow crossed into a different reality.
When he says "let's go home?" He means HIS home, his universe.
Now the question is which universe is the Prime Universe we're all used to seeing? That remains to be seen.