Hi @jesusem,
Please refer to screenshot below to create the flow:


Note:
Please add your company domain on the variable "company domain", and add your company name on the variable "company name".
The expression in the Compose as below:
split(concat(triggerBody()?['RequiredAttendees'],triggerBody()?['OptionalAttendees']),';')
The expression in the Condition as below:
@and(not(contains(items('Apply_to_each'), variables('company domain'))),contains(triggerBody()?['Location'], variables('company name')),not(empty(items('Apply_to_each'))))
The expression in the Condition 2 as below:
@equals(variables('contain outside company attendees'), true)
When a event is created,the flow would run successfully as below:

Best regards,
Community Support Team _ Alice Zhang
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