I’d recommend the Innuos Pulse. It’s new and contains Innuos’ latest thinking, is compatible with Roon, and comes with their Sense app that gets top marks for both usability and sound quality. And at $3250 it’s well under your $5k price target.
Or you might consider this used Pulsar that’s only two months old, and as long as the warranty is transferable this is well worth a look…
https://www.audiogon.com/listings/lisb68e0-innuos-pulsar-media-servers
Best of luck.