Swipe up.
Tap Chrome.
Tap New Tab.
Tap Tenor favorite icon.
Type in "Rick and Morty yes".
Find GIF.
Long press, open in new tab.
Long press, open image in new tab.
Go to address bar.
Long press, copy entire URL.
Swipe up and over to go back to Amethyst.
Reply.
Paste copied URL text.
Better to copy the image itself and have your client make a new link that's less likely to rot.
I don't know think there's a need to download the image and re-upload it to another service. That's more time consuming for an interaction that should only take seconds. If my GIF reply disappears in a year, I don't think anyone is going to be overly upset.
If you copy things the "right" way in iOS it can happen automatically, and that should be more durable.