Okay, that's a super-weird problem, yeah.
11:45:32.353: Output 'adv_stream': Number of lagged frames due to rendering lag/stalls: 8587 (1.7%)
11:45:32.353: Output 'adv_stream': Number of dropped frames due to insufficient bandwidth/connection stalls: 4324 (0.8%)
11:45:32.353: Video stopped, number of skipped frames due to encoding lag: 141/512180 (0.0%)
You do have some minor encoding lag, and your connection is dropping frames every now and then. But for some reason you're getting rendering lag... on a 2070 Super, running as Admin (which should activate the GPU priority override, preventing rendering lag).
About the only times I've seen that are when the GPU or motherboard drivers are REALLY hosed, the person is using an incredibly heavy and laggy browser source, or the PCIe slot that the GPU is in is being run at like 1x or 4x rate instead of the full 16x it should be at. Or the system has a major underlying problem at the OS or hardware level.
Step one in troubleshooting. Create a new Scene Collection (at the top of OBS). Just have ONE scene, and add your gameplay source to it (so your capture card). See if the issue persists. This is attempting to rule out the browser source as an issue.
Step two. Download GPU-Z and run it, and post a screenshot of the output it provides. We'll be able to see what's going on with that.
We'll proceed from there based on what happens. :) Make sure to either reply to this or @tag me so I get a notification on your reply, and can follow up.