This has been an interesting thread to follow. I remember the first one from the OP (and went back to read again) so first off, if 2017 CVO Street Glide (Bill) wasn't worried about his warranty with the mods to begin with, he shouldn't be concerned about it when something goes wrong. Looking back, the original subject received input that warned him about aftermarket mods and the loss of said warranty with aftermarket mods so he knew the deal going into this game.
If the dealer actually did tell him they would honor his warranty even after the mods and then recanted when the caca hit the fan, bad on them. However, the OP was warned not to trust the dealer's statements either.
We aren't privy to the conversations between the OP/dealer/HD so we only have the OP side of the story. Ranting on this site is a given. He has every right to be upset that his applecart was turned over as we all are from time to time. However, he can't say he went in blind to the facts.
The MoCo has had and it appears will continue to have issues with customer service, reliability, manufacturing defects due to faulty choices and/or poor workmanship in their 3rd party suppliers, etc. The MoCo got their hand slapped/wallet drained by the EPA and 2017 was the first lock down of this type of issue. The OP knew it going into his purchase so the MoCo, in this instance, followed the warranty guidelines and owners manual warning to the consumer...warranty will be void if....
It's like touching the 500 degree plate at Ruth Chris when the waiter/waitress had already warned you it was hot. It stings but it's on us for not heeding the warnings of the experienced.