I think I can think of a circumstance: the a/c at FL350 is at the altitude above which climb or increase climb RA are inhibited, for performance reasons.
In that case, if we assume a cooperative scenario, the climbing aircraft will I believe be told to stop climbing (via an RA) and the FL350 aircraft will just hold, which may just mean a TA since no action is required? Because the only RAs that can be issued for the higher a/c are descend cases, which dont help resolve the conflict.