Again if you did some research prior you would know that all signs point to him being an NHL defenceman rather than not, You failed to elaborate on what level of risk; although if you did it would be contrary to your agenda.
Being an NHL defenseman isn't some high bar when you're talking about the team getting him having to trade their best defenseman.
His point is valid. Even Justin Schultz dominated the AHL to an even greater degree than Liljegren is now. No one had an ounce of doubt that he'd be an NHLer but he fell pretty far short of what he was expected to become.
Doing well in the AHL is not a guarantee of success.
I'll do a more local example. Brendan Leipsic tore up the AHL and now he's a journeyman NHLer with all speed, hands, but no finish playing for one of the worst teams in the league.
If you want Lindholm you need to be willing to part with an asset that Anaheim can confidently bank on for the future. Not cross their fingers on.