Football is business and Manchester United is business. Ed is not buying players for fun, he is a businessman, he wants to be convinced. Jose could not. So Ed bought no CB.
Its up to Jose to find the right investment, which convinces Ed.
Sorry but you do not understand the inner working of the football business, the manager is either given a budget which is made up of the fee for the player and the wages.
So for instance if Jose was given 100 mill budget each season, the fee and wages are offset within the 100 mill, so if jose signs Dalot fo 20 mill and Dalot picks up a wage of £20,000 per week, on a 5 year contract, this equates to just over 1 mill a year and just over 5 mill in 5 years, leaving Jose with 74 mill left to spend in the current window.
Woodward is not qualified to veto Jose's deals, he can however fail to make purchase due to the selling clubs, hiking up the prices. What should normally happen is Jose see's a player or a player is brought to his attention by the club scouts, a decison is made by the manager or the manager and DOF, then Woodward enter into the fray to negotiate.
In normal practice, there would be 3 to 5 options, if option 1 is not acheiveable, then Woodward attempts to purchase option 2 or 3.
Man Utd is not Southampton, who acts as a feeder club. It's not Jose job to convince Woodward of investments, but to provide him or with a shortlist, and Woodwards job to provide the manager with the tools to do the job.