While at first glance there seems to be various contradictions between the accounts of Jesus' last week, there actually are not any meaningful contradictions. In fact, it is the seeming contradictions that point us toward a better understanding of these events.
So it is in other scriptures and prophetic teachings as well. Rather than doubting the veracity of accounts, we can doubt our doubts and seek for truth.
Understand that the Lord teaches on many levels and that He will try to help us see plain truths that are hidden. Just as many ancient events and observances pointed toward His day, many signs and teachings point toward our day, the last days before He comes again. Those who are trying to see and understand will be rewarded for their efforts.
Finally, there were likely people who did not understand the full meaning of things they were being asked to do 1500 years in advance. For example, the High Priest likely did not understand the import or full meaning of raising the first sheaf before the Lord on the day of resurrection. God is a perfect planner. There are things we are asked to do that we do not fully understand either. Hopefully we do not have to wait for 1500 years for greater understanding. If we can believe in Him, believe that he has all power, knows all things, and that we cannot comprehend all that He can, that is enough.