[FTS] pIndexLookup Encounters Server Write Timeout Instead of Returning an Error

While doing some testing of the /pindexLookup endpoint in Postman, I kept running into a 503 error with the following response: 

{{

{"status":"fail", "error": "server write timeout"}

}}

 

Server build: 7.6.0-1785

Request was sent through Postman to http://localhost:8094/api/bucket/{{bucket-name/scope/scope-name/index/index-name/pindexLookup}}

Authorization was basic Username/Password. Username and password are both valid and worked with other endpoints.
Bucket name, scope name, and index name are all valid, and worked fine with other endpoints. 

Body used a valid{{ "docID" }}of{} { "docID": "hotel_5848"}{}, which matches a document that should be included in the index. 

I used the following index definition with the travel-sample bucket: 
{
"name": "travel-sample.inventory.travel-test",
"type": "fulltext-index",
"params": {
"doc_config":

{ "docid_prefix_delim": "", "docid_regexp": "", "mode": "scope.collection.type_field", "type_field": "type" }

,
"mapping": {
"default_analyzer": "standard",
"default_datetime_parser": "dateTimeOptional",
"default_field": "_all",
"default_mapping":

{ "dynamic": true, "enabled": false }

,
"default_type": "_default",
"docvalues_dynamic": false,
"index_dynamic": true,
"store_dynamic": false,
"type_field": "_type",
"types": {
"inventory.hotel": {
"dynamic": false,
"enabled": true,
"properties": {
"reviews": {
"dynamic": false,
"enabled": true,
"properties": {
"ratings": {
"dynamic": false,
"enabled": true,
"properties": {
"Cleanliness": {
"enabled": true,
"dynamic": false,
"fields": [

{ "docvalues": true, "include_in_all": true, "index": true, "name": "Cleanliness", "store": true, "type": "number" }

]
}
}
},
"content": {
"enabled": true,
"dynamic": false,
"fields": [

{ "docvalues": true, "include_in_all": true, "include_term_vectors": true, "index": true, "name": "content", "store": true, "type": "text" }

]
}
}
},
"pets_ok": {
"enabled": true,
"dynamic": false,
"fields": [

{ "docvalues": true, "include_in_all": true, "include_term_vectors": true, "index": true, "name": "pets_ok", "store": true, "type": "text" }

]
}
}
}
}
},
"store": {
"indexType": "scorch",
"segmentVersion": 15
}
},
"sourceType": "gocbcore",
"sourceName": "travel-sample",
"sourceUUID": "8f866261438f8b0d415a437552f3ae99",
"sourceParams": {},
"planParams": {
"maxPartitionsPerPIndex": 1024,
"indexPartitions": 1,
"numReplicas": 0
},
"uuid": "766ddce5d41a3b41"
}
The question is, why does the request encounter a server write timeout, rather than returning an error that the document couldn't be found, or returning the expected response for the endpoint, when the document is present in the index?