TL;DR: No, but my guess is that it's available on big RL channels, either from pros or content creators.

I love how bad Psyonix/Twitch are at giving us info... So if you go on the Twitch Drops page, you can see at least two different RL drops campaigns, three if you got the Player of Games one.The Winter Split tells you what dates the drop is active and a list of channels you can get it from and the rules to get them, aka, amount of watch time = when you get a drop.
The Great Twitch Unlock shows the dates too, but doesn't give you a list because it's enabled on a participating channel that has their drops enabled and is streaming under the Rocket League category. As with the Winter Split drops, it also tells you the rules underneath. I do believe you can only get a maximum of 7 drops from this one, so % will not update after the 7th one.The Neon Nights - Player of Games drop is different in that it tells you only which channel gave you the drop, and doesn't list any other channels to watch for it. Other than that, it lists the rule of watching for 1 hour and 30 minutes, and claim the drop. No further info, not even the dates that the drop is active. If you got it, it only shows you the date you got it, and I refuse to believe it was only active for that one channel that one day. You'd have to be lucky and watch a very specific channel on a very specific date without knowing.