[1.14.4] Custom Commands - Get original unparsed string from EntityArgument

Hi, I am making a custom command that included an EntityArgument but I don't want to actually parse that argument into entities. My custom command is like a custom teleport command that figures out the destination and then calls the real teleport command with the same source EntityArgument and the destination that my command figures out. I don't to just grab a string because I won't have the suggestions and validation that I normally get when using EntityArgument but I can't pass the parsed entities to the real teleport command as far as I know. Is there something I'm missing here? How can I get the raw string that was typed into the EntityArgument rather than the parsed version, or is there a better way to do this? In 1.12.2 I just kept that particular argument and passed it to the teleport command along with my generated destination.

Thanks