So, regarding Ertz, if you can trade him (obviously needs to be healthy) for anything at all, before June 1st, you can actually lower his dead cap from $10 million in 2023 to $6 million and have $6.6 million in cap savings vs releasing him and having a $2.6 million savings. This is why he doesn't need to be released just yet. It's costing zero to keep him until after the draft, as long as you deal with him before June 1st.
As for Conner, you should still deal with him before June 1st, but again, like Ertz, if you can swing a trade for anything (even if you agreed to pay part or most/all of his salary) his cap savings is $6.4 million vs just releasing him and saving $695k.
For both, let things play out in the draft and see what happens on the other side, but before June 1st.