SOQL filter in Power Query

Okay, so here's your entire WHERE clause translated to M code:

Table.SelectRows(
    Custom1,
    each [IsDeleted] = false
    and [Status] = "Completed"
    and [OwnerId] <> "00558000003jg6TAAQ"
    and [CreatedById] <> "00558000003jg6TAAQ"
    and [WhoId] <> null
    and [SalesLoft1__SalesLoft_Type__c] <> "Hot Lead"
    and [SalesLoft1__SalesLoft_Type__c] <> "LinkedIn - Research"
    and [SalesLoft1__SalesLoft_Type__c] <> "Note"
    and [SalesLoft1__SalesLoft_Type__c] <> "Other"
    and [SalesLoft1__SalesLoft_Type__c] <> "Reply"
    and
    (
        (
            not
            (
                [SalesLoft1__SalesLoft_Type__c] = ""
                and [Tasksubtype] = "Task"
                and [Type] = ""
            )
        )
        or
        Text.Contains([subject], "Sales Navigator")
    )
)

Here's the original WHERE clause formatted, so you can see more clearly where the brackets etc. are and compare to the M version:

WHERE
isdeleted = FALSE
and createddate >= THIS_FISCAL_YEAR
and status = 'Completed'
and ownerid <> '00558000003jg6TAAQ'
and createdbyid <> '00558000003jg6TAAQ'
and whoid <> ''
and SalesLoft1__SalesLoft_Type__c <> 'Reply'
and SalesLoft1__SalesLoft_Type__c <> 'Hot Lead'
and SalesLoft1__SalesLoft_Type__c <> 'Note'
and SalesLoft1__SalesLoft_Type__c <> 'Other'
and SalesLoft1__SalesLoft_Type__c <> 'LinkedIn - Research'
and
(
    (
        not
        (
            SalesLoft1__SalesLoft_Type__c = ''
            and Tasksubtype = 'Task'
            and Type = ''
        )
    )
    or
    subject like '%Sales Navigator%'
)

Pete