Actually, from RTFA, it appears they were entitled to them. From the article:
...defendants [IRS thugs] threatened to ‘rip’ the servers containing the medical data out of the building if IT personnel would not voluntarily hand them over,” the complaint states...
By giving them the servers, the IT personnel effectively waived the fourth amendment protection. As painful as it might have been to watch, the IT personnel should have said "NO! I do not consent to you taking the servers." rather than hand them over. If the IRS thugs then did rip them out, now you have a fourth amendment violation.
It's the same thing if a cop tells you to empty your pockets/purse/backpack etc on the hood of a car. The proper response is "I don't consent to searches." and do nothing. The cop may do it anyway, and you shouldn't resist if they do, but now you have an illegal search, which puts you in a better positon in court.