Combining IF Statement along with CONCATENATE if it exists

Trying to combine and IF + Concatenate together. I'm running a report right now for my company where we grab samples from different water locations, but due to COVID-19 we aren't allowed in some specific locations and therefore have to get a water sample from a nearby hydrant.

I have all the locations and hydrants in one spreadsheet as data, and in my main tab I have an empty cell where someone may put (YES/NO) and if they put YES then another cell will fill with the hydrant name along with the location.

My issue is I have to have both this data combined in one static cell if "YES" is put, for example...

Location: LOC-3 John Street 
Hydrant used?: YES
Hydrant (auto filled): LOC-3 HYDRANT 3333

Full location name (if YES): LOC-3 John Street LOC-3 Hydrant 3333
Full location name (if NO): LOC-3 John Street

This is the code below that I'm using in order to return the location name, can't figure out where or how to throw concatenate in there without getting an error back. Thank you in advance for your help.

=IF(OR((AND((A6<>""),(D6<>""))),(AND((B6<>""),(D6<>"")))),IF(A6="",B6,A6),"")