Your plumbing is just black plastic that slips inside the tank and then is tightened by the SS clamp that you're seeing. You might be able slip the plumbing back into the tank some, but you'll probably find it hard to move.
When you replace the valves, do both at the same time. I think you can buy both from Camping World for about $25.00 and even cheaper on line. Use a 1/4 drive socket set with a swivel to get to the nuts and bolts. When reassembling, use some Vaseline to hold the seals in place and help slide the valves back in. The Vaseline won't hurt anything.
Lastly, the valves will leak when debris gets stuck in the seals. This can be caused by pushing the valve shut while there is still junk coming out. Make sure you do a good rinse before closing the valves. A little WD-40 on the valve rods (where handle is attached) will help the valves work better and smoother.
Don & Mary
2014 Newmar Dutch Star - All Electric - 450 ISL
2016 GMC Canyon 4WD Crew Cab