The silencers can move. You want them pinched up in the contact areas as much as possible. If they're not long enough, you may need a longer set. They work like the Chinese finger traps. When idle or pulled they're tight, but squeeze them and they make room to slide up.I lubed all contact points with silicone grease.
Do the pro kit silencers move up and down? if they do then it is possible the spring compressor could have slid it down a bit.