I have the LXE version of the grill. It has a 1 lb bottle connection to the regulator, and then the regulator connects to the grill with what appears to me to be a nonstandard fitting.
Since the TT LP connection is post regulator (low pressure), connecting that to the high side of the grill regulator won't work. So, it would have to be connected to the nonstandard connection on the grill which I don't know how to do.
You might be able to saw off the regulator and attach flare connectior to the raw pipe, but that's out of my area of expertise. (KA BOOM)
There is a kit to tap into the high side at the LP tank and attach a hose to the high side of the grill. That's probably the best way to make a somewhat permanent connection, but the kit is around 60 dollars.
Or, just give up and buy the little bottles like I do.