I don't know if it's the same or not but Shazam said it was the slowed and reverb version of the song.
Spotify link for the OP: https://open.spotify.com/track/0OttkMAdUb9HqLctwmzj9I?si=zndSsdQARHKNLd1mHBc3pA&utm_source=copy-link&dl_branch=1
(Tip: As I said, you can use Shazam (it's a music searching app for times like these. Google play link: https://play.google.com/store/apps/details?id=com.shazam.android (Unfortunately it's only for mobile phones but there are websites that do the same job too))