TI Map Domain entity to EmailEvents

let dt_lookBack = 1h;
let ioc_lookBack = 14d;
let EmailEvents_ = materialize(EmailEvents
| where isnotempty(RecipientEmailAddress) and isnotempty(SenderFromAddress) and TimeGenerated >= ago(dt_lookBack) and DeliveryAction !has "Blocked"
| project-rename  EmailEvents_TimeGenerated = TimeGenerated
| extend SenderFromDomain = tolower(SenderFromDomain)
| extend RecipientEmailDomain = tolower(tostring(split(RecipientEmailAddress, '@', 1))));
let SenderDomains = EmailEvents_
| distinct  SenderFromDomain
| summarize make_list(SenderFromDomain);
let RecipientDomains = EmailEvents_
| distinct  RecipientEmailDomain
| summarize make_list(RecipientEmailDomain);
let TI = materialize(ThreatIntelIndicators
| where TimeGenerated >= ago(ioc_lookBack)
| extend IndicatorType = replace(@"\[
| \]
| \""", "", tostring(split(ObservableKey, ":", 0)))
| where IndicatorType == "domain-name"
| extend DomainName = tolower(ObservableValue)
| extend TrafficLightProtocolLevel = tostring(parse_json(AdditionalFields).TLPLevel)
| extend IndicatorId = tostring(split(Id, "--")[2])
| where DomainName in (SenderDomains) or DomainName in (RecipientDomains)
| summarize LatestIndicatorTime = arg_max(TimeGenerated, *) by Id, ObservableValue
| where IsActive and (ValidUntil > now() or isempty(ValidUntil))
| extend Description = tostring(parse_json(Data).description)
| where Description !contains_cs "State: inactive;" and Description !contains_cs "State: falsepos;");
(union
  (TI
| join kind=innerunique (EmailEvents_) on $left.DomainName == $right.SenderFromDomain),
  (TI
| join kind=innerunique (EmailEvents_) on $left.DomainName == $right.RecipientEmailDomain))
| where EmailEvents_TimeGenerated < ValidUntil
| extend ActivityGroupNames = extract("ActivityGroup:([^,]+)", 1, tostring(parse_json(Data).labels))
| summarize EmailEvents_TimeGenerated = arg_max(EmailEvents_TimeGenerated, *) by Id, RecipientEmailAddress
| project EmailEvents_TimeGenerated, Description, ActivityGroupNames, Id, ValidUntil, Confidence, DomainName, RecipientEmailAddress, SenderFromAddress, Subject, ConfidenceLevel, Type, TrafficLightProtocolLevel, DeliveryAction, DeliveryLocation, EmailDirection
| extend Name = tostring(split(RecipientEmailAddress, '@', 0)[0]), UPNSuffix = tostring(split(RecipientEmailAddress, '@', 1)[0])
| extend timestamp = EmailEvents_TimeGenerated