Expression using last function with threads channel id

Summary:

Hello all,

I have a report with some incidents.

My goal is to add a column to this report and display a custom value in it based on last threads channel id. For example: threads.chan_id = 5. So my expression would look like this: if(last(threads.chan_id = 5,'value1','value2'))

The main table is Incidents that is joined to threads table.

I tried paying around but still did not managed to make it work. The main problem is that I need to take into consideration just the last threads channel with id 5. I also found an article about