I keep my snakes in tubs not tanks so when I say tub, think tank.
Feed in the tub. The associating hands with food thing is mostly a myth. Snakes are intelligent and not likely to make that mistake. What can help is having feeding tongs. I use tongs to feed, and hands to do anything else. In a slightly tipsy moment I decided to use a clump of white paper towels to clean the side of the tub once with a ball in there.... No tongs, so it didn't try to go for the moving ball of white stuff.
Clutter that tank up with stuff if you can't switch to something smaller. The plastic vines from hobby lobby, or the pet store would work.
What are you using to measure the temps? If it's the plastic round stick to the glass things, they are very inaccurate.
There red is absolutely hope! Don't give up!!
And ive had luck with asking toddlers small children to play first. Shake shake Shake it out. Get them to run jump shimmy and Shake. Then red light! Embrace the age, don't fight it lol.