Thank you for the information.Yep,
The frame hasn't been repaired. This extra part has been welded originally bye the owner because radical frames were know for being wick around the head tube.
Actually, the owner was a car mecanics who two kids racing dh. As a nerd, he made plenty of enhancments inclusif frame and rockers modifications, internals of the fork.
Be sure the frame has non failure.
That’s a shame that the frame has been messed with, is not in its original form, has been repainted and isn’t a co-factory frame.