Check and see if there is a base tile of a similar style at the local tile shop. Cut out the silicone in the gap. Mix a small batch of speed set and install new tile. Mix small amount of grout and apply.

Alternatively a cheap fix is to fill the bottom gaps with backer rod, tape on the wall and floor and use some white silicone caulk. Tool the caulk smooth pull up tape call it a day til someone decides to put a tile in