I was offered the exclusive program first and I declined, I felt like it wasn't worth it to throw away years of building an audience on webtoons for a platform I don't know much about and I can't guarantee an audience on. The non-exclusive program sounds good though since there isn't really any risk with it.
Is your comic on the platform yet?
I think maybe because it's way different from their regular comics that's the reason they contacted you about it? they're probably trying to expand their library into more genre's.
On another note, I've asked them some questions regarding the ownership and the ownership is completely the creators for the non-exclusive program and you'll be able to take your comic off the platform if you want. (I haven't asked about the exclusive program though)