The horses don't budge at Guardian's guidance, one even whinnying and shaking its head a little as its bridle is tugged. When Rolda takes over, the lot of shy equines suddenly become rather compliant, straining in their harnesses to pull the sledge forward. There's a bit more resistance the runners hit the smooth stone floor but not enough to bring everything to a stop. After about a minute of pulling the entire obelisk is inside the entrance tunnel.
Dram just watches as its pulled inside, standing off to the side and divesting himself of the armor of the recently killed, save for the gambeson, gloves and boots. When the tail end of the sledge has cleared the doorway, he gives a "c'mon' nod to Septimus and Guardian and begins tugging on the door. Now that the inside can be seen, a massive crossbar on a central circular pivot makes it easier to grab onto and pull into position.
Spoiler: OOC
The lock's like an interior garage door crossbar, just way bigger: