I'd love to help, but I can't see the video for some reason. I really really really hate using harsh chemicals, should be your very last resort. Some bugs are actually beneficial, wish I could see! In any case, one thing you can do right now that will contain the issue if to dress the top soil with an inch or two of washed sand, expanded clay pebbles, perlite or my favourite - growstones (recycled glass), or something similar, even lots of regular rock pebbles. Soil bugs lay their eggs on the first inches of moist soil, so the idea is to create a dry layer where eggs won't thrive and hatch, and bugs need to go way too deep to reproduce and most wont make it. You will also want to bottom feed to help keep the top soil as dry as possible. Add lots of yellow sticky traps too to catch them.