One can see venus with the naked eye during the day - but not when it is near the sun.
I expect that a red filter would get rid of some of the scattered atmospheric light. A telescope should be able to see some of the brighter stars during the day.
But to get the scope so near the edge of the sun that you can measure that arc-second displacement, you'd have quite a lot of sunlight entering the telescope. The atmospherically scattered light in that region is quite intense.
One can use an "Occulting Disk" but they are of limited effectiveness. When the sun is in the sky, hold your hand out at arm's length, then block the sun with your thumb; you'll see that the skylight is quite bright around your thumb. That's not from the solar corona - not much of it - but from atmospheric scattering.
'Es ware deshalb von grosstem Interesse, bis zu wie groszer Sonnennahe helle Fixsterne bei Anwendung der starksten Vergrosserungen _bei Tage_ (ohne Sonnenfinsternis) gezehen werden konnen.'
My translation:
'It would therefore be of the greatest interest [to know], until how near to the sun bright fixed stars could be observed, under the largest magnification and by day (without solar eclipse).'