Overpaid can be argued about, as I said. Last two seasons, Gourde averaged 56 points, which makes 5.16m look like a pretty solid deal. This season he's in our bottom 6, which makes 30 in 70 look respectable.
Playing 2nd line for MTL or any other team, he's likely move back into 50+ point territory, which again, makes 5.16m a very adequate cap hit.
As for Johnson, he is literally averaging 49 points his last 4 seasons. Rule of thumb says 1m per 10 pts, roughly. Which makes his 5m cap hit seem pretty reasonable, too, no? And that is not even considering that for at least parts of that he was also playing third line and that he can be used on both special teams units.
No idea why you're so desperately trying to make Johnson and Gourde seem overpaid/worthless, but the numbers say differently.
Again, just because they are dispensable for TB and would help navigate their cap situation, doesn't mean they are worthless/wouldn't fetch a return in a trade. As I said, probably would be for 70 cents on the dollar, but that's fine.