Just stuff the frog with some weights. I had a frog that had a good leak in it last summer and if i forgot to squeeze it after a couple casts it would become a submersible frog that slowly sank. I had gotten lazy one day and just decided to fish the frog back underwater on a cast cause i forgot to squeeze it and low and behold a 3lber came and ate it. I tried the subsurface frog for a little longer that day for no more takers. I bet it you stuck an oz of lead in a frog you could fish it in a manner they are definetly not used to seeing.
Also don't forget baby stripers, I'm sure they are taken down by the bass in the delta and lakes with stripers.