First, I agree his testimony would be very interesting, though that info will not be released. The DA is going to sit on all evidence and testimony connected to the GJ.
But also, Ive nothing but empathy for the horrors the FW family faced in accusations. However, theres no record of having been threatened by R attorneys. I dont doubt FW was smart enough to figure out that JR in particular was quite dangerous in terms of using his wealth and legal team to attack others.
Primarily the Ws, and in particular FW, were thrown under the bus by the Rs, as well as by strange people who came up with so many lies, that one can still find horrendous web pages accusing FW. Even in her testimony, PR made sure to let the case investigators know that PW had a jacket like hers (implying that it could be PWs jacket fibers left on the duct tape and garrote.)
From what Ive read the Ws were also maligned by quasi-journalists seeking sensational copy. It is likely for this reason, that FW and PW have avoided any kind of public statements or airing of opinions about this case. There are still way too many crazies connected to this case. moo
IIRC, GS and SS were the last couple to see the R's, since the R's were delivering presents after the W's party.