No, I wouldn't think the condo's mortgage would cause the error, as long as you reported that one as a secondary home and this one as a primary or vice versa.
If this mortgage was the only one for that home, you can leave off the mortgage acquisition date entirely. Doing so should not impact any of the calculations. If a mortgage interest limit applies, that is calculated based on the date that you originally purchased the home, not when the mortgage was acquired.
