On one hand, the Yamaha is not a expensive antique but on the other hand if you are going through the effort of refurbishing it, why not do a good job?
In the sporting goods industry, we saw lots of damage to plastics, coatings, rubbers, etc. from exposure to certain lubricants and chemicals. Sometimes the product manufacturers used the wrong lubricant accidentally or "discovered" an incompatibility after a lot of warranty claims. This was still a problem in the 90s and I sense the problems have declined over time but am out of that game.
There are just so many materials & coatings it is difficult for a consumer to know what lubricant to use. Sometimes the damage does not manifest itself for quite some time.
And there is some risk of mixing degraded lubricant with a different new lubricant.
If you care about the Yamaha piano lasting, you can ask Yamaha. Alternatively, just try the Yamaha lubricant. If you don't care too much... In any case, I would try to clean off the old lubricant before applying new lubricant.
