I'd be curious about which two products and why can't 1 do both. Not questioning your situation, but just trying to understand.
For your question, I've only run into this with a mistake. We had a product doing compression for everything, but someone added in full backups with native algorithms. The easiest thing to do here for a recovery was convert the log backups back to native.
I think we tested the restore, and as along as the restore with Norecovery/standby was done, we could use the third party product to add the log restores.
NOTE: I would never endorse or recommend this. We could go from a bad situation to a horrible one if someone makes a mistake switching between products. When you restore, stress and pressure become an issue, so we want the absolute easiest, simplest thing ready. I would argue vehemently against using two products.
The being said, if I had to do this, I'd practice often, so the staff understands what to do.