Mac mini (2018) start-up monitor issues

I have a Mac mini (2018) with the 3.2ghz 6-Core i7, integrated graphics, etc. My monitor is a LG 27UK650-W bought at the same time. I have posted on this before, but have since gone through a number of trials to figure the issue out, and wanted to re-post with more information.

The initial problem: At some point, I don't know exactly when other than months after the purchase, I began to have an issue where when I would power the computer off and return some time later to turn back on you could see the light at the front of the computer turn on and the machine was clearly on, but the monitor would be blank. I would try the PRAM/NVRAM reset and what have you but it only worked after a series of forced resets. When waking from sleep it was fine, but often a restart would trigger the problem and certainly shutting it off. Eventually, no amount of resetting could fix it so I took it into the Apple store a couple of months ago.

Apple resolution: After tests were done, Apple confirmed the logic board was out and because it was within a year of purchase they replaced and repaired free of charge. In doing so, my computer was wiped clean and reset which was fine because I figured it further cleared any issues that may be getting in the way. I brought my computer home, booted it up and it was fine and I figured it was fixed.

The recurring problem: At one point I was going out of town and had shut my now fixed computer down. When I returned, the same thing started happening. I couldn't get it to work, and it was the same as before where the computer would come on but the monitor would not come on so I could see what was going on. So I took it back into Apple right away given it was hardly a month after repair. After tests and looking at it they actually found there was no issues even after trying a number of monitors and/or TVs. So I said maybe it was me and took it home.

The problem continues to occur after bringing it home. There was one interesting thing I did notice however, and maybe it was just coincidence. But when my computer would again not work, I would turn it off, take it into my living room and plug it into my TV where I would use my Apple TV power cord and HDMI, and the computer would show on the screen. Then, when I would shut it down and take it back to my desk and plug into the monitor it would work.

Additional information: I have a Logitech keyboard and mouse, but also got a wired Apple keyboard so that doing the SMC reset, etc. is possible even if the wireless setup isn't working. I also have a PC connected to the second HDMI port, and never have any issues with that display working. I have even switched the HDMI ports to make sure it isn't a port issue, and switched HDMI cables around to a series of different ones to make sure it is not a cable issue. I have upgraded Mac OS and kept everything updated, the computer is mounted with plenty of air space around it, and I have even made sure to only use the USB-C ports as one post postulated there could possibly be interference created by some design of the USB ports. (I was going to try everything)

What I would like to know: I have read a number of posts about issues with the Mac mini and display devices. But I can't seem to find any that result in a resolution. So anything anyone possibly has to resolve this issue, any advice on perhaps certain HDMI cords that work but others that don't, any thoughts on perhaps the monitor I have for some reason being one that doesn't work with the Mac mini well, any suggestions for how to go around the problem and not reset my computer all the time, or just any possible thing at all would be great. I feel weird if its something with the monitor when it works well sometimes, and always works well on my PC connected to the other port, and the monitor overall seems to have great reviews and notes of people using it with the Mac mini. My only option now really is taking everything to the Apple store for a third time with my monitor and all cords and just be told they don't know.

Any direction here is helpful. Thank you.