If Ole were to stay, I think we would have gone back for him. However, with our new direction, signing him is not worth it. In short term it doesn't even guarantee nothing. He would improve our RB for now, but our chances to make top 4 is low. At his age, soon we would have to get a younger permanent RB anyways. Dalot maybe below the required standard for long term purpose, but he's serviceable for now.
Ole was trying for quick fix for his trophy drought without a long term vision for style. Signing Trippier to complete the team only makes sense then.