Question I need help getting my EG4 System to work

I am not clear on what you mean by where the power is going. It is not going anywhere as far as I see. It is a lowering of how much power is coming from the panels. No changes in my house power usage.
I did an experiment yesterday, where that number was going down (from around 2600 watts) to around 1400 watts (so it was on its way down) ...so I turned on my EV charger, bumping my power usage from around 400 watts to 8,000-ish. And the watts coming from panels jumped instantly from that 1400 to over 3,000.

This lowering of power coming from the panels happens daily between noon and 1PM like clockwork. There is no change, normally, in my house power usage when this happens. 
I have been over this with EG4 Tech support and they can't figure it out. They want me to hire an electrician to come and get on the phone with them about it. But that will probably cost me hundreds of dollars which I do not want to spend. Espeically because they may not be able to figure it out anyways.
I think it is a flaw in the equipment somehow.

Thank you for your comment, by the way! Appreciate it.

Any excess power can only go to one of three places. Either the batteries, the house loads or the grid. The inverter can only pull power from the solar panels or the batteries. The inverter (or GridBoss if available) can also send grid power to the house loads or charge the batteries. The panels can only show power if the inverter can put that power some place. i.e. battery, loads, grid. If the batteries are fully charged then no excess power can go there. If the inverter is set up to not sell power to the grid or it's set to only send a limited power to the grid, then power can't go there. If you are drawing minimum power to your house loads then that will be the power you will see being produced by your solar. i.e. power can't flow if it has no where to go. You proved this by turning on a high power additional load (EV charging) (House). So I think everything is working properly with the settings you currently have. Providing a snapshot of your monitoring home page for all three conditions, will show where the various power flows are going. At that point we can then see if any settings changes are needed based on what your requirements are and what you are expecting your system to accomplish in the end. The settings affect where power is sourced from (Solar, Batteries, Grid) and where it goes to (Batteries, Grid, Load). I'm assuming that the house, or a fixed number of it's loads, are wired into the back-upped loads connection and maybe none or a small amount of remaining loads are connected to Non-Back-upped connection. 

I would suggest doing a download of your data history. This can be found in your computers EG4 web page and go into its Data, Data History tab. Then just click on the Export Data (for that day) or Export data for the week (8 days). You should do this for both your inverter and GridBoss if you have both. You can then edit out your inverter & GridBos's serial number column. Then attach it here so it can be reviewed. Each row will contain data for all measured functions for intervals of 4 to 5 minutes. Typically the inverter updates every 5 minutes while the GridBoss updates every 4 minutes. Not having this information is just a speculation on what's actually happening with your system and reviewing it will hopefully point to a root cause.