Its just a thought, but if the previous times youve met for a drink he has been down then i would say do something else.
Get Ice cream and walk around the harbour instead maybe?
something side by side and slightly active without anything between you is generally quite good for making people more comfortable. Theres some information around on body language which gives some guidance on settings that make people feel more open.
like i said its just a thought.
Both mid 30s, 2 young kids BD 7sep14 XW moved on long ago, now living with OM1 D paperwork in progress