Which source code is that exactly that you see there? It could possibly contain a clue to the cause.
It is returning the first 60 lines of the source code of the referenced site. Just the WordPress code for the site you’d see if you ‘view source’ when you’re at the site.
Does this also happen with any other wp command? Maybe even if you just call wp?
To me it sounds more like some component (theme or plugin) of your project is generating an output that is not implemented correctly. This could also have an unfavourable effect in the frontend, depending on the constellation, even if you can’t see it at the moment.
To find the cause, I would recommend that you first change the theme as a test and rule it out as the cause. If it also happens with a standard theme, deactivate the plugins used.
sigh. simple obvious solution. it was a plugin. all is working as expected now. thanks.