ATC Watcher:
Your memory fails you , no, responsibility in IFR for terrain avoidance is always with PIC except when under radar vectoring . (ICAO DOC 4444)
Actually U.S. ATC procedures are much more restrictive in this regard than most of the world as a result of the 1974 TWA 514 CFIT accident.
ATC is responsible for assigning an altitude at, or above the MEA if the flight is on a published route. If the flight is cleared direct then en route ATC (which was the case here) must assign at altitude at or above the ATC center's MIA chart.
The crew also had a duty to challenge this improper clearance because the approach chart had a wealth of operational altitude information.
The ATC clearance per the U.S. FAA controller's manual should have been not less than 4,300 since the flight was cleared direct to ZEDAG.
The preferred clearance would have been, "Cleared direct ZEDAG, maintain 4,300 [or higher], expect clearance for the RNAV Runway 19 approach."
A second compliant clearance would have been, Cleared direct ZEDAG, cross ZEDAG at 4,300 [or 4,300 or above], cleared for the RNAV Runway 19 approach."