[PC SSE] Anyone had issues with Helgen opening with Skyrim Sewers SE installed?

So, I didn't see anything touching Helgen in the Sewers .esp, not meshes either, or anything in the vicinity until Whiterun. It also has no scripts, although it might use vanilla scripts at places.

Some quick backstory. I installed Sewers some time ago, thought it was one of the better mods on LE, didn't do much this time though, killed a few skeevers. Got tired of Frostfalls ridiculous exposure, didn't feel like modifying it with the menu because that just cripples the mod so uninstalled it and Campfire.

Started a new character, show up outside the cart, conversation starts but horses are somewhere else. Quit and coc to Whiterun and try again and it works. Anyway, later start a bunch of other characters, cart's stuck every time, horses elsewhere, also notice that Ulfric doesn't load. Quit to menu, start anew and it works again, but every time there are some issues in opening Helgen. Horses aren't where they should be - horse near the tower at the chopping block is now nuzzling up Hadvar. After getting near the arch before entering the interior of Helgen, Hadvar and I ragdoll, although we get up and continue, something I've never seen before. I forget what else.

Anyway, it doesn't make sense to me. Sewers isn't know for script load because it doesn't have any. It doesn't change meshes in the area. The only conflicts it has are with Skyrim and Update and some lighting mods, the latter overriding it anyway. And the former conflicts are with the areas it changes, which again doesn't include anything near Helgen exterior. No race record changes, nothing with horses.

Any ideas?

edit: oh I should say, I know anything can set off 'cart troubles', even 0 mods. But well, there's clearly some connection.

edit: should also probably mention that disabling Sewers has Helgen opening running perfectly.