"All reports of committees and motions to discharge a committee from the consideration of a subject, and all subjects from which a committee shall be discharged, shall lie over one day for consideration, unless by unanimous consent the Senate shall otherwise direct." The fact that motions by the full Senate to discharge are permitted, with the qualification of one-day layover unless waived, makes them valid. Presumably layover was waived by unanimous consent as delay would achieve nothing.

Parliamentarily, this is not used except in extreme cases, but deadlock would qualify. I was surprised to find that Dan Honemann, one of the editors of Robert's Rules Newly Revised 12th edition, is busy answering questions like this on the official forum: "If a committee has been instructed to report at a particular meeting, the chair at that meeting should call upon it to submit its report at the time designated in the standard order of business (assuming that this is the prescribed order of business). If the committee fails to submit a report at this time, as instructed, a motion to discharge it will be in order, and will require only a majority vote for its adoption." Presumably deadlock qualifies as a failure to submit/report at the designated time.