Multi DB causing slow load times

I have a WP multisite with Multi DB setup. I also have a testing location with the same theme and set of plugins running, but without Multi DB. The one without it experiences page load speeds of around 500ms. The network with Multi DB setup a averages 5-7 seconds per page load. Again, everything is the same with both networks except for the database architecture. I’m wondering if it has to do with the fact that I currently have 1 mysql user assigned to 4096 databases. Please advise.