Currently on version 4.4.5 from the curseforge and have it installed onto the server, once joining it gives the prompt on which origin to use but can't use the arrow buttons to select a different one. I've tried it on a singleplayer world but can't do it either...

4.4.5 seems to be the version of your modpack, there is no 4.4.5 version of Origins (even for the Forge port).
Make sure the issue is caused by Origins, and find out what the version of the mod is.
Also, if you're on Forge and not Fabric, head there instead of here.