Responses

To ppl following this question: it was Doha himself who inserted his tape. He saw Bada insert a tape in one of his playthroughs so he got curious. When he found a black cassette player he secretly inserted a tape, not knowing that it was a save point. And along the way, that was also when Seongchan's tape was removed because his tape was in the black cassette player when Doha found it. Doha ejected it to put his own tape (again, at that time he didn't know what the tapes purpose were).
I hope this helps (づ ̄ ³ ̄)づ
Dropping this here again in case yall need a refresher
https://docs.google.com/document/d/1fyfND0KcEKCLjX-4X9l66b9U6diWfaakpy1NOWcA8mY/edit?usp=sharing