Cracked Travertine tile repair - Tile Advice

[cmjb13]

Fitted our hallway with Travertine tile a few years ago. Followed up with doing the Kitchen floor with the same tile about 18 months ago.
2 of the tiles that meet the hallway tile were cracked.
I removed the tile and I could clearly see the backerboard gap.

Before I put replacement tiles down, can someone please tell me what I should do with the gap?

Use backerboard seam tape?

 

[Smiler5714]

Fitted our hallway with Travertine tile a few years ago. Followed up with doing the Kitchen floor with the same tile about 18 months ago.
2 of the tiles that meet the hallway tile were cracked.
I removed the tile and I could clearly see the backerboard gap.

Before I put replacement tiles down, can someone please tell me what I should do with the gap?

Use backerboard seam tape?

I would for sure use the backer board tape with adhesive but beforehand, get a couple of screws on either side of the joint into the deck below the board to make sure there is no movement once taped and filled.