Rewrite SQL Query 2012 - 2008

I would like a script that replaces the following query that only runs in SQL2012 but need this to run in SQL Server 2008R2. Data that comes from the EVENT_TIMESTAMP column varchar(100) is in the following format '2016-12-12 14:25:36.789Z' SQL Server 2012 Query: SELECT DATEADD(HH, 10, IIF(CHARINDEX('Z', e.[EVENT_TIMESTAMP]) > 0, SUBSTRING(CAST(e.[EVENT_TIMESTAMP] AS CHAR), 1,19), SUBSTRING(CAST(e.[EVENT_TIMESTAMP] AS CHAR), 1,24))) AS DateTime, e.EVENT_TIMESTAMP FROM dbo.WMB_MSGS AS e Note: Not all entries in EVENT_TIMESTAMP column have the 'z' eg. 2016-10-12 14:75:36.819 at the end hence the need to filter. ************* Below is what I have so far you choose to use this or not but note the query. declare @event table (ID varchar(max)) insert into @event SELECT event_timestamp FROM dbo.WMB_MSGS WITH (nolock) Where EVENT_TIMESTAMP > '20170101' select ID, replace(ID,'Z',''), --Ignore entries that don't have a 'z' in them. cast( replace(id,'Z','') as datetime), dateadd(hour,10, replace(id,'Z','') ) From @event -------------------------------- Maximum I am offering for this query is $70