I posted this as a Reply but it's so important that I think it needs a new post of it's own, so here goes:
Currently Spectrum and 'their friends' at Roku are not playing in the sandbox together. I accidently deleted the app yesterday on one device and it deleted it on all my devices on my Roku account. I knew the Spectrum app is currently not available on the Roku channel store so I knew I was in trouble (I have 2 Roku TV's and 2 streaming sticks). First I called Spectrum and was told they had a workaround for the issue. Just log into my Roku account on my computer and go to 'Add A Channel' and the channel code would be prepopulated in the channel code dialog box. I tried it while I had the Spectrum support person on the line. No dice. The code did not prepopulate. Then the Spectrum dolt told me I'd have to call Roku to get the code from them (wow, really?!?! Spectrum doesn't know what it is?!?!). He even gave me the phone number (how nice, huh?). So, I called Roku only to get an automated answer that Roku is not providing ANY telephone support because of Covid (seriously, hi tech Roku can't figure out how to set up people to answer the phone working at home when the entire rest of the world is doing just that with their employees?!?!). LAME! So, I started searching the Roku site even more than I already had and found a line that mentioned if you don't have a channel code you need you have to get it from the channel provider! Needless to say, now I'm getting steamed! Thanks Spectrum! I searched all over the internet and couldn't find the channel code ANYWHERE. Soooooooo, I called Spectrum again. This time the support person said he would send me an email with the instructions on how to add the channel in. He sent me two. The subject line of the first email was "Options for Viewing Spectrum TV App During Roku Negotiations" which is the same junk you find on the Spectrum website telling you the other ways you can watch Spectrum instead of using Roku (duh!). The second email was titled "Spectrum TV App Update for Roku Users". I looked at it briefly while the I had the support guy on the line still and it was just basically the same add a channel info the first support guy told me about. Then the guy told me to use the "Use this link.*" link in the email. I clicked on it. It took me to the Roku log in screen. When I logged in it took me to the add a channel dialog box and, voila, the channel code WAS PREPOPULATED! I clicked on 'Add Channel' and presto! The Spectrum app was back on my Rokus!! Now, I'm not sure if it is an account specific code, or if you've never had the Spectrum app on your Roku account if it will work, but, for what it's worth it worked for me and here is what I know:
The email link took me to this webpage https://my.roku.com/signin?sessionTimeout=true&next=https%3A%2F%2Fmy.roku.com%2Faccount%2Fadd%3Fchan...
The Add Channel webpage it then took me to is https://my.roku.com/account/add?channel=tjw26c21
The channel code that prepopulated is tjw26c21
Hope this helps for others who are struggling with this SUPER FRUSTRATING ISSUE!! Oh, interesting note for other believers out there. The second support tech's name was Elijah!