I went through this last year. I got into LMU-DCOM in mid December (the day before my last final actually!) while enrolled in a one year master's program. I finished my classes for that fall, but after contacting DCOM and finding out that completing the program was not required by them, I dropped the program for the spring and enjoyed a semester off 😀
Many questioned why I did that- why not get the extra degree, you're half way there, they said. I said, why spend another $6,000 when I already have lots of undergrad debt and TONS more debt coming my way. It's essentially your call.
If I were you, here's what I would do:
-Report your enrollment status to AACOMAS, or at least your future DO school.
-Email someone or call someone in admissions and see if dropping out can affect your acceptance.
-If not, either drop out now and cut your losses on money for the first semester (I would only do this if your program wasn't very costly, if you aren't super interested in the courses, or if the grades might actually hurt you) or drop out after fall semester.
-If they want you to at least finish these classes, do your best to crank out nothing lower than a C, but preferably at least a B.
Having these fall classes under your belt will most likely do nothing but help you next year. The few classes I finished last fall were some of the most helpful for my basic sciences this year. Bottom line, though, you CANNOT CANNOT CANNOT (did I mention cannot?) conveniently "forget" to disclose your enrollment status to your future school. It's considered an omission on your application, even if you started after you applied because you can update AACOMAS and the school both. Things like this get people dismissed from their schools- promise.
Good luck!