As awesome as it would be, the sad truth is we're more than likely never going to see these games come to fruition.
Freelance Police is still LucasArts property. Telltale can't finish the game, nor can they use anything from it, just like with Hit the Road. Even if LucasArts wanted to finish the game (and they don't), they no longer have the Sam and Max license. You may ask yourself "Can't Telltale and LucasArts work out a deal?" Probably, but it wouldn't benefit either of them as much as what they're doing now. Telltale can make Sam and Max games by themselves just fine without having to share the profits with another company, and LucasArts does well enough by releasing an endless sea of Star Wars crap.
Plunge Through Space is a different story. Infinity Machine, the company developing it, went bankrupt, so I don't really know its legal status. Did it revert to LucasArts when they re-acquired the Sam and Max license? If that's the case, could it belong to Telltale already since the Sam and Max license is now theirs? Did Steve Purcell get the rights after Infinity Machine went bankrupt since he owns Sam and Max? Are the rights just floating around, belonging to nobody, waiting for someone to get their hands on them? I don't know. But I do know that if Telltale was able and willing to finish Plunge Through Space, it would've happened by now.