Yes you're right Viz knows there are fans of the old dub BUT are there enough fans to justify spending time and money on a new release ? - I would say they have decided there is not.
That's why I said - if you want to convince Viz there is a SUFFICIENT market for them to work on the release make a petition.
A few emails / posts on a forum / questions at conventions DOES NOT make a business case for working on a new disc release.
While I'm glad you have thankful you have provided some concrete solutions....it's sadly too late.
The real time to convince anyone to release the old dub was
before Sailor Moon was re-licensed, not several years afterward.
By releasing their new dub Viz has staked its claim on the series.
Most of the people who actually did want the old dub either gave up on the series or just adjusted to the new dub. The new dub killed much of the old dub market by absorbing existing fans and driving the last remnant of fans away. Vocal Sailor Moon fans rejecting the old dub made sure that it would never see the light of day by convincing people the old dub was nonviable.
Given that the expense of a new dub would be greater than the expense of digging up the old one, if they were going to release the old dub, they would have done that
first. Fans who wanted a new dub would still "support the franchise" in hopes of getting a new dub some day, while those who loved the old dub would buy it. If there wasn't enough money generated, then Viz would be have been out less money than if they decided to redub the series and it flopped.
Instead, Viz, convinced by hardcore fans that a redub was the best way to recoup its money, decided to roll the dice with the hope of a greater reward. Given the delay in Stars dub...I have a sneaking suspicion than that this risk failed...and so did any hope of the old dub.
If people want the old dub to be released so badly then go and prove it to Viz with hard numbers. Comments on FB / Twitter / questions at conventions doesn't prove a thing / is not an indicator of actual sales. It might not seem like it but I'm sure it would take at least $30,000 - $50,000 of capital to re-release the old dub on disc not to mention the approvals process that they have to go through and Viz aren't just going to spend that time and money without any reason.
The best you can hope for is to get Viz to run a kickstarter to raise the funds needed to re-release it. If they know they have backing then they're more likely to go and do it.
EDIT - OK here you go ->
Sign the Petition
Lets see how many signatures it gets
( Not that I'm personally interested in having a copy of the dub but hey ho I'm interested to see if this can get any traction )
As you mentioned, though, they aren't going to do it unless they recoup the losses, and they created a situation where it is impossible to do that and release the old dub. They erased the old dub through their greed, instead of thinking of maximizing profits.
For anyone who actually does want the old dub released...I think it should be clear now why any pro-old dub "hysteria" was understandable in hindsight.