Keep in mind that scanners do what they do because they feel like it. They're not organized and they're certainly not on a payroll. Because of that, the only way to get a firm non-affirmative answer would be to have every one of our thirty thousand members say, "no, I don't have a copy." I think we'd all agree that would be a horrible waste of everybody's time.
If you think of a request as "if someone happens to see it," that's great. If instead you're asking for some scanners to seek out, pay for, and put in the (almost literally back-breaking, surprisingly, if you haven't tried it) labor to scan a big pile of books you'd like to read...well, it's probably not going to happen, and prodding probably won't help all that much.
Our recommendation is always that anybody who wants or needs to see a specific scan shouldn't rely on the kindness of pseudonymous strangers (imagine asking when a specific Wikipedia article is going to get written or updated), but rather acquire and scan the books on their own and (hopefully) post them for the rest of us. That's where almost all of our contributors come from, after all (as Tilliban suggests), people who wanted to see specific scans that weren't showing up, and it's a small community of pretty dang nice people.
But no, I'd guess that nobody is sitting on a secret cache of old comics, just waiting for someone to ask for one before they scan it. There's also probably nobody with an overflowing piggy bank waiting for someone to ask them to buy comics for them.