No, i don't, but i don't think that's the issue since there are several other modpacks on the steam workshop as well.
Most "copyright" systems act only when requests are made, so just because others do it too doesn't mean you won't get in trouble for it.
Your modpack contains a ton of large mods by active mod authors, so I wouldn't be surprised at all if some of them have complained.
Which, let's be honest, is perfectly reasonable. You're taking their work without permission, aren't giving proper credit, and there's no way to easily tell in such a highly modded game which mod does what, so even the argument for indirect exposure can't be made here. I have no doubt that you have good intentions, but this clearly isn't the way to do it.
If you want to create a collection of mods, do so by using the proper steam feature:
https://steamcommunity.com/workshop/browse/?appid=281990&browsesort=trend§ion=collections
That's less convenient for the user, but it respects the work that authors have put into their mods.