i have pt many children and i dont stay in the house for days//weeks on end - def cant if it is no 2 being being pt as always out and about with no 1
carry on with same daily routine as you have with activites and then warn the groups you attend that you are pt - all should/will be fine as obv child friendsly groups (hopefully)
take potty and plenty of spare trousers/pants and towels if doing a music class where sit on cushions etc and place on potty every 20mins then 30mins then hourly as gets better
you say you started before and gave up after a day, you are prob going to have a few days of 7/8+accidents till your dc gets to know the feeling of needing a wee, so dont give up if you have a bad day
if not dry after 2weeks and having lots of accidents then your son is not ready
2.5 is quite early for a boy, and esp so at 2 if you tried several months ago - tho my dc was done at 2.5 as needed to be dry for nursery and was done within 2 weeks, though the first few days we got through so many pants
obv both nanny+mum need to be doing the same stuff, and once you start pt dont put in nappies/pull ups as confuses the child
good luck - tbh it is normally the nanny who does the pt and the parents who dont continue it at weekends/days they not working and that really annoys us nannies, all our good work is undone by 2 days in nappies
so suprised your nanny isnt keen,unless like nannyl says she thinks he isnt ready
why do you want your dc to be pt now?is he showing signs?