HEROD'S TOMB AT HERODIUM (if that's what it is) is covered in a sort of travel article in Arutz Sheva:

Herodium: Judean Palace where Herod Lived and Died

by Shalom Pollack

(IsraelNN.com) The location of Herod’s tomb remained a mystery until an innovative archaeologist set his sites on an overlooked side of the Judean fortress palace of Herodium. After a 35 year search, Professor Ehud Netzer felt he was able to announce to the world that he finally found what he was looking for – the royal tomb of King Herod the Great (73 BCE – 4 CE). The tyrannical leader who murdered Jewish sages and even his own family members was secretly referred by them as Herod the Wicked.

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These Arutz Sheva travel pieces tend to be a little careless. I don't remember all the details of this tomb story but I did spot the following. The article says:

Although he knew that he was hated for his tyranny, Herod nonetheless made his wish on his deathbed: “Gather all the rabbis to the adjacent room. Announce that when I die, the rabbis will also be killed. Thus, the day that I die will not be a happy one. In fact, all will pray for my health” This last order was not executed, but such was the man’s evil intentions to the very end.

This story is from Josephus (Antiquities 17.6.5) and it actually refers to "all the principal men of the entire Jewish nation," not the rabbis:

He commanded that all the principal men of the entire Jewish nation, wheresoever they lived, should be called to him. Accordingly, they were a great number that came, because the whole nation was called, and all men heard of this call, and death was the penalty of such as should despise the epistles that were sent to call them. And now the king was in a wild rage against them all, the innocent as well as those that had afforded ground for accusations; and when they were come, he ordered them to be all shut up in the hyppodrome, (9) and sent for his sister Salome, and her husband Alexas, and spake thus to them: "I shall die in a little time, so great are my pains; which death ought to be cheerfully borne, and to be welcomed by all men; but what principally troubles me is this, that I shall die without being lamented, and without such mourning as men usually expect at a king's death. For that he was not unacquainted with the temper of the Jews, that his death would be a thing very desirable, and exceedingly acceptable to them, because during his lifetime they were ready to revolt from him, and to abuse the donations he had dedicated to God that it therefore was their business to resolve to afford him some alleviation of his great sorrows on this occasion; for that if they do not refuse him their consent in what he desires, he shall have a great mourning at his funeral, and such as never had any king before him; for then the whole nation would mourn from their very soul, which otherwise would be done in sport and mockery only. He desired therefore, that as soon as they see he hath given up the ghost, they shall place soldiers round the hippodrome, while they do not know that he is dead; and that they shall not declare his death to the multitude till this is done, but that they shall give orders to have those that are in custody shot with their darts; and that this slaughter of them all will cause that he shall not miss to rejoice on a double account; that as he is dying, they will make him secure that his will shall be executed in what he charges them to do; and that he shall have the honor of a memorable mourning at his funeral.

Background here.