there is no sealant in the track for the awning, the seal is created by tension. so maybe check that your awning is very tight when open, as a loose awning WILL leak water.
I had a leaking awning with water splashing in through the sail track, the awning was tight but with heavy rain and moderate wind the awning was lifting slightly and splashing in.
I raised the front of the van slightly which drained the water out of the track and completely stopped the leak.