From my own experience, managers or agents (the title is less important) know little about guidance or mentoring. Of course money's a factor, but to allow it to override instincts about making healthy decisions is negligent at best.
As we're all seeing now, decide in haste is something that young players need to be guided away from. They have short careers, and some have even shorter careers if injury or stupidity cross their path. I wonder what Cole or Sinclair must be thinking at this moment? Wise agent vs ungrateful club? If either have someone they can turn to for advice (not their agents) now's the time to buy them a coffee and talk.