No. He ran out and acquired 86-DOS, from Seattle Computer Products. It's easy to have something when you buy it already complete.
And DR had CP/M-86.
MS still had to make modifications to Tim Patterson's 86-DOS before it shipped as PC-DOS 1.0 - source: Paul Allen's Idea Man autobiography.
Same thing, he did the needful to have something to give ibm.
DRI did not have CP/M-86 at that time which is the reason Tim Paterson developed 86-DOS in the first place.