Mongot's nightly test runs against mongo-master are failing in certain pipelines with $search inside lookup with the following error - 

FAILURE: Command failed with error 4946301 (Location4946301): 'PlanExecutor error during aggregation :: caused by :: undefined slot accessor:6' on server localhost:37017. 

An example of a run can be found in this patch: https://evergreen.mongodb.com/test_log/mongot_master_ubuntu1804_mdb_master_large_e2e_tests_655872871e2d175fd4b51569_23_11_18_08_15_03/0?test_name=397256bf32667ff1348f15b9b536f3e2&group_id=#L1

Full patch run link (ignore "MQL" related failures, those are unrelated): https://spruce.mongodb.com/task/mongot_master_ubuntu1804_mdb_master_large_e2e_tests_patch_106d4d5fc0bdb55cff530f115023ec9de1cf5bea_655bf7381e2d17b422621953_23_11_21_00_18_24?execution=0&sortBy=STATUS&sortDir=ASC

Pipeline from these mongot tests are failing:

• https://github.com/10gen/mongot/blob/ec3d6217dc20feb4b1ace78c02f3d380fd998ef7/src/test/integration/resources/index/subpipeline-search.json#L3-L112
• https://github.com/10gen/mongot/blob/ec3d6217dc20feb4b1ace78c02f3d380fd998ef7/src/test/integration/resources/index/subpipeline-search.json#L195-L286
• https://github.com/10gen/mongot/blob/ec3d6217dc20feb4b1ace78c02f3d380fd998ef7/src/test/integration/resources/index/subpipeline-search-facets.json#L3-L544
• https://github.com/10gen/mongot/blob/ec3d6217dc20feb4b1ace78c02f3d380fd998ef7/src/test/integration/resources/index/subpipeline-search-facets.json#L815-L1445
• https://github.com/10gen/mongot/blob/ec3d6217dc20feb4b1ace78c02f3d380fd998ef7/src/test/integration/resources/index/subpipeline-search-facets.json#L1761-L2304

Each of these tests have the following structure:

[
{$lookup: {pipeline: [$search, ...]}},
{$sort}
]