Minecraft – Title command will not appear (1.13)

Curly brackets are for NBT data (player/item NBT reference, world/entity NBT reference). For example, you could use:

/testfor @a {OnGround:0b}

To check for players that aren't touching the ground.

What you are wanting to do (check for players within a radius of some coordinates) should be done with target selector arguments instead. These use square brackets, and would look something like:

/testfor @a[x=-651,y=66,z=-633,r=1]

As this is part of the selector, you could also get rid of the testfor and simply use:

/tp @a[x=-651,y=66,z=-633,r=1] -660 66 -632

You may also want to look into the 1.9 command blocks. A repeating blocks would be easier and more efficient than your fill clock, and same with conditional blocks instead of comparators.

execute has an if score subcommand that lets you easily compare any two scores, and run a command if the test succeeds. The following commands should work for what you want to do:

execute if score Team_Red Gold > Team_Green Gold run title @a title {"text":"Team red won!","color":"red"}
execute if score Team_Red Gold < Team_Green Gold run title @a title {"text":"Team green won!","color":"green"}
execute if score Team_Red Gold = Team_Green Gold run title @a title {"text":"It's a draw!","color":"gray"}