As calaprfy said the tourists are far away there’s a picnic area if you zoom out from the outside of the science lab you will see it on the right of your screen.
The plant thing has been an issue for awhile the patch before Seasons has plants changing stages and becoming harvestable at 6 a.m. and only if you’re on the lot at that time. The scientist ?? career starts at like 9 a.m. so unless and until they put it back to the plants becoming harvestable once you enter the lot as it was before the Seasons patch (and really wish they would) the mod Logion suggested is the best fix. The trade off for this though is if you’re not on your home lot in the timeframe of that mod your sim will likely not be abducted by alien sims as that tends to happen around midnight or so. So it’s up to you to decide if that’s for good or ill. Otherwise you need to grow the necessary plants at your home lot and take them to work with you in your inventory to make the required recipes and skip the goals involving gardening at work.
I have seen the invention constructor bug and I do hope they fix it. It’s one of my favorite animations.
