Debtors are people who owe you money. The word you are probably looking for is “creditors”, who are people you owe money (e.g., corporate bondholders.)
But, while it's closer, stockholders aren't those, either.
There are two things you could disagree with but you don't specify which. You can disagree that Tesla set this goal for itself, or you can disagree that the number 5000 is arbitrary.
To disagree with the first part, you'd need to show that the 5000 figure came from an external party, do you have such a source for this?
To disagree with the second part, you'd need to show that there is something significant about the number 5000. Is your claim that there is some significance to the number 5000?
If you can't substantiate the claim that some external party gave Tesla the goal to make 5000 vehicles per week, and you can't substantiate the claim that the number 5000 has some fundamental significance when it comes to car manufacturing, then you have no grounds to refute the statement that Tesla set this arbitrary goal of 5000 for itself.
Wasn't it in multiple letters to shareholders? It is literally an update to debtors on the company's position, far from arbitrary.
Were Tesla required to give an estimate? Nope. But doing so may be used to attract further investment into the company, so it is far from innocent.