the fruits are fine, this is how i feed frut to my birds as well

mushy doesnt change the nutritional content just the texture so long as they arent rotten they fine.
and yes they can drink things other than water, but water needs to always be available in their cage even if something else is offered, the water should never leave the cage.
i give my birds juice all the time, freshly made (we have a power juicer) and also store bought, but it needs to be 100% with no additives, no added sugar, no perservatives and so on... otherwise it defeats its purpose and they can not process those chemical additives.
i also give my birds non caffiene tea, this does not mean decaffienated tea which is regular tea that has had the caffience decreased, its not caffiene free, nothing that has caffiene can ever be caffiene free

green teas and the such that naturally have no caffiene (herbal teas are good)