I have both of these scanners as well, but also newer models, and I don't recall if the Wx frequencies have to be programmed in to the PRO-92. I know they do in some models.
What you could do is simply go to channel 000, and manually program in the local Wx frequency. What do you get?
The post from scansalot52 is correct; the PRO-92 after sitting around for days might need to "warm up". I've seen several weird problems with this scanner from oxidizing connections between the circuit boards to it just needing to be powered before it starts to receive.
What concerns me at the moment is that you are having trouble with two different scanners, which are quite different designs. I must wonder what the common denominator is.
In order to pick up something, all you need to do is program the frequency and that's it. Don't program any tones (they only LIMIT what you pick up) and set the mode to FM. If you're trying to monitor a TRS, put in the active control channel frequency, set the mode to FM and sit on that channel in MAN mode. Do you hear "data"? If not, no other programming is going to help. If so, then proceed.