The OP is actually considering two separate trips (one in a few weeks and another in August). Even if the first re-entry is successful (which would then restore legal status), it's possible that the CBSA officer could only authorize a short stay. This would then mean that the OP would have to apply for an extension and hope that it is approved.
You'd like to think that when CBSA sees that a person has taken action to remedy their problem, by applying for sponsorship, that would add substantial credence to their case. Having to decide between staying in the basement, or traveling to see an ailing family member can't be an easy decision...although it should be.
Talk about being between a rock and a hard place!