Please don’t DIY when it comes to book repair!
And this is also why the staff at the library will often stress that patrons should not attempt their own repairs of library books. The “repair” often does more damage than helps, and won’t actually save you from being fined for a repair or replacement fee. This was so heavily damaged that we ended up withdrawing it, and probably just bought a new copy. But now it has a second life in my office as a great example of “what not to do”!