N1ql How to use a GSI when doing a join

This is my explain output

[
{
"#operator": “Sequence”,
"~children": [
{
"#operator": “IndexScan”,
“index”: “fernando_idx_company_time”,
“keyspace”: “Session_Bucket”,
“namespace”: “default”,
“spans”: [
{
“Range”: {
“High”: [
"“4b602472-44e6-4c22-a674-047484d588b8"”
],
“Inclusion”: 3,
“Low”: [
"“4b602472-44e6-4c22-a674-047484d588b8"”
]
}
}
],
“using”: “gsi”
},
{
"#operator": “Parallel”,
"~child": {
"#operator": “Sequence”,
"~children": [
{
"#operator": “Fetch”,
“as”: “Session”,
“keyspace”: “Session_Bucket”,
“namespace”: “default”
},
{
"#operator": “Nest”,
“as”: “aryEvents”,
“keyspace”: “Events_Bucket”,
“namespace”: “default”,
“on_keys”: “(Session.aryEvents)”
},
{
"#operator": “Nest”,
“as”: “aryPageRules”,
“keyspace”: “PageRule_Bucket”,
“namespace”: “default”,
“on_keys”: “(array_star(aryEvents).causeId)”,
“outer”: true
},
{
"#operator": “Filter”,
“condition”: “((((((Session.companyId) = “4b602472-44e6-4c22-a674-047484d588b8”) and (not any Event in aryEvents satisfies any rule in aryPageRules satisfies ((((Event.result) = “form-completed”) and ((Event.causeId) = (rule.ruleId))) and ((rule.pageGroup) = “homedefenders.com Quote Form”)) end end)) and any rule in aryPageRules satisfies ((rule.pageGroup) = “homedefenders.com Quote Form”) end) and (((Session.aryBreStatus).homedefendersQuoteBreadId) is missing)) and ((Session.lastEventTime) < (now_millis() - 300000)))”
},
{
"#operator": “InitialProject”,
“result_terms”: [
{
“expr”: “self”,
“star”: true
}
]
},
{
"#operator": “FinalProject”
}
]
}
}
]
}
]