In hindsight, Thomas Markle Sr. definitely needed more guidance from the Palace. But...Doria Ragland got exactly the same amount of help and SHE hasn't colluded with press..
Did Meghan need guidance too ? The two situations are not comparable, but take Daniel Westling for example. Not only did the King of Sweden take nine years or so to consent to his marriage to CP Victoria, but also Daniel received extensive "grooming" from the Swedish Royal Court, including tutoring in constitutional law, royal history, and etiquette and protocol. The latter specifically (i.e etiquette and protocol) was also part of Sofia Hellqvist's now famous "princess classes".
Comparisons aside, I don't think Kensington Palace and Clarence House have quite met the standards we would expect from the PoW's and Prince Harry's households in the run-up to this wedding. It is not surprising that the British press is now turning against the courtiers for alleged lack of professionalism and letting things get out of control.