Transaction Group -> DB to Memory Tags

One of my plant is entering process quality records into a database. The records are not necessarily put in to the DB in a timely manner, but there is a representative timestamp column; the table columns end up as Lane, Unit, Date, ProcessValue1, ProcessValue2, ProcessValue3, etc. The memory tags are named as such: Lane_Unit_ProcessValue1, Lane_Unit_ProcessValue2, etc.

My goal is to bring these values into the Ignition historian so that it can be aggregated and consumed alongside other historian data by external tools. I'm currently using a Standard Transaction Group to pull the most recent record (using a select max(timestamp) query tag as trigger tag). That is working well, but the problem is around the timing in the historian. Is there a way to set the "timestamp" part of the memory tag qualified value? I need the Lane_Unit_ProcessValue1 tag value & timestamp to match with the source DB record.

I attempted to set the Timestamp property as part of the 'Edit group tag window', but this did not work (note that group's mode=>DB to OPC):