Uhum!
Denny probably didn't know that there were different violin basses and marvelled at the stamina of his boss in the Star Club with an EB hanging from his shoulder for 12 hours on end!
The weight of the Höfner on those long Captagon-fuelled Hamburg gigs must have been an argument (along with the fact that it didn't look silly played leftie and that Paul came from a guitar scale).
It's not unlikely that The Beatles came across an EB while in Hamburg. Reputedly, the first owner of an EB in Germany was James Last - the later Easy Listening orchestra leader - when he was still a bassist, he came from Hamburg and had a top notch reputation as a (initially acoustic) jazz bassist at the time. He later sold his EB to Ladi Geisler (who equipped it with a P split coil and used it for his click bass sound before totally switching to Fender) who was playing with Bert Kaempfert, another Easy Listening king who recommended The Beatles to Decca and also produced their first few singles with (and without) Tony Sheridan in 1961/62 - prior to Brian Epstein and George Martin taking them under their helm.
That bass on Ain't She Sweet sounds nothing like the bass on early Beatles EMI/Odeon recordings, but very Bert Kaempfert-like the way it is raised in the mix, Kaempfert dug a loud bass, it was part of his recipe to make "dance music with no annoying sounds". We all know how guitars sounded back then!
