Right now $rankFusion inside a $unionWith/$lookup on a view will not work on standalone, yielding the following error message:

No resolved namespace provided for <underlying_collection_name>

The sharded cases work, so we only need to fix the behavior in standalone.

The queries were referencing have a structure like:

db.coll.aggregate([{$unionWith/$lookup: { from: "view", pipeline: [{$rankFusion}] }}])