Rink boards cover-up

Not sure if there is a cheap solution, but I used to figure skate and I swear the rink would cover up the boards for ice shows with things like these fabric covers:
https://www.georgiaexpo.com/product/dasher-board-skirting-covers/.
If your rink already hosts alternative events like yours, they might already have board covers in storage. Maybe you could ask if you could use them for free or rent them? Or, ask other local rinks/figure skating clubs where they rent them.

For a space that large, nothing that covers it up will really be affordable. Whether it's pipe and drape or flowers, whatever you use to cover it up will be costly due to the labour and the amount of coverage you require.

An alternative would be to embrace it and enhance the wood panel look with a theme. You can go classic with some rustic decor to compliment the wood. If you and the fiance are into hockey, that's a great theme to incorporate.