Cracked/Wet grout - suspect improper kerdi-drain install?

[BuilderWoes]

First off, this is an awesome community that I happened to stumble upon for my search for help. As you can tell by my name I am pretty disappointed with the tile in the shower. The grout around the drain appears damp for days after one use and the grout around it has cracked away.

This is on a 3-yr old house but this specific shower never used more than 10 times. This was the model house - so it was sold "as-is." I am on mercy street; currently trying to plead a case to the warranty team as the shower was never used and it appears the tile flooring was improperly installed.

My inexperienced suspicions are:
1) The thin set under the kerdi drain was insufficient: slight flex -> premature grout failure
2) The drain itself is set too low causing the pitch of the tile and grout around it to be too steep
3) The tile around the drain is cut too narrow, I can't even fit 1/16 around the bottom left corner of the grout leading to water penetrating

What am I looking at for repairs?

[ss3964spd]

Welcome, J,

It does look like the drain was set too low. Even though some type of Schluter drain was used it's difficult to determine which one without knowing how the shower pan was built. If Schluter's typical bonding flange drain was used I'm a bit befuddled as to how they could have installed it so low relative to the other tiles immediately around the drain.

The cracking grout does suggest movement, either with the mortar (or possibly lack of) the tile is set in or in the substrate below the mortar.

Regardless of the poor tiling job, if the water proofing was done correctly and the drain installed correctly water penetration through the grout and into the mortar directly under the tile would be a non-issue.

As for repairing it, it seems that at a minimum all the tile around the drain area would have to be removed to determine what exactly is under the tile. If it's a bonded flange Kerdi drain, the circular flange is pretty large diameter and removing the tile and mortar might also remove the fleece on the flange that the mortar bonds to, or the fleece of the membrane that overlaps the flange. If the fleece does come off with the tile and mortar you'd not be able to get new mortar to bond to it.