The dynamic air formulas work on Gen5's too. However, I believe the filtering that SiriusC is working on should be MUCH easier because Gen5's have the Flow Factor PID [2376] that tells numerically how much of the input is being scaled from MAF or VVE...basically we don't have to try to calculate or emulate the internal algorithm from the ECM for steady state or transient.
So you can then choose to filter out everything the ECM deems as not steady state (like we are doing here for Gen4)...or build that into the formula itself to back calculate MAF and VVE as GRG already did:
https://www.youtube.com/watch?v=WoXTmdTQkpE
Note, I have not tried this on a Gen5, so I cannot comment on how well I like it or how well it works.