I mostly agree with all the positive reviews out there. Sweet and hot, very nice characters and relationships.
I would like to add for people who might not know, that omegaverse rules are by their fictional nature completely moldable to the author's whims. There's a lot of works with similar rules, but like werewolves or vampires, everyone has their interpretation. That's why even in very similar abo works you'll find different percentages of the secondary sexes among the population, different state of laws and views regarding omegas, or different advancements in regards to suppressants, among many details.
Which is why, being able to erase a mate bond is not "illogical", as long as it's decided as possible by the author. The story doesn't go into any details, so it's possible that the mark may be "overwritten" by biting over it (I have seen abo works where it happens). But the character might have simply wanted to cover the bite with his own mark, like many people cover bites or hickeys on the bodies of those they want to mark possession and/or dominance.
I think it doesn't really matter, as I see the scene as mostly being here to show that the characters' bond is unbreakable because they want to stay together. I find that way more romantic than being forced together forever against your will.
Although I also find the character of the rapey guy in question to be lacking, we don't get enough backstory to explain his change of mind.