Distributed Bass Array Speaker Placement

I recently moved to a new house with a large basement room with the dimensions of 18’ x 28’ x 8.5’. Mains are Wilson-Benesch Vectors placed a good distance from the side and front walls. They are crossed over to a 4-speaker distributed bass array with a JL Audio CR-1. Low pass and high pass are both at 80Hz with a 4th order slope. There is no option for delaying either the mains or the subs. More details are available on my Audiogon system page.  

My research (https://www.audioholics.com/subwoofer-setup/multiple-subwoofer-setup-calibration-1) indicates that a good arrangement is to place each subwoofer in a corner or at ¼ of the room width on the front and back walls. I am concerned that this placement could make the time delay between the mains and subwoofers output audible.  My question is will placing the subs ¼ of the room length on the side walls provide most of if not the same outcome as placing them on the front and back walls or in the corners? This would be my preference since it will make the subs pretty close to equidistant from the main listening position. Or something entirely different?

I do not wish to employ DSP.  Been there, done that with my Devialet 400 and my goal here is to go pure analog. It sounds pretty amazing now and is certainly superior to what I had before.