When a pub's indoor dog policy is unclear or restrictive, the garden is almost always the reliable fallback. Outdoor pub gardens are overwhelmingly dog-friendly across the UK, regardless of the specific venue's indoor rules, simply because the hygiene concerns that apply indoors mostly don't apply to an outdoor seating area.
Water bowls left out near the garden entrance or by outdoor tables are common enough to be a genuine cultural marker — pub staff in dog-friendly areas routinely keep one topped up without being asked, especially during warmer months.
The one consistent courtesy expected in return: keep the dog on a lead, settled beside your table rather than wandering between others, and clean up immediately if there's any mess on the grass or paving — the same basic etiquette that applies to a pub's indoor areas, just with more room to work with outdoors.