1st time DM here. My level 3 party (DnD 5e) used the immovable rod and some rope to escape through the window of a collapsing tower in the latest session. This left the immovable rod out of range of the Sorcerer's mage hand.
The wizard wished to use his spider familiar (re-skinned as a large ant due to arachnophobes in the group) to climb the rope and press the button. At the time the party were being rushed by a group of guards, I made a hasty decision that this was not possible and they ran for cover.
The wizard has since argued that this should have been possible as with a strength score of 2 the familiar has a carrying capacity of 30lb (2x15) & therefore is stronger than the mage hand previously used to carry the rod. I pointed out that as a spell mage hand works differently but agreed that in future this would be possible - with a strength check from the familiar, considering it's a tiny creature attempting to press the button whilst hanging from the rope tied to the rod, 100+ft in the air.
The wizard is unhappy about this, arguing it should be possible without a check. Should I allow the familiar to do things similar to this without a strength check? If it were a simple button on a wall/ the ground, I would be more inclined to allow it.