Hes 23 now. Next year (the last year of his deal) he'll be 24. two years max on tag puts him at 26 how is that about 30. Wtf are you talking about?
His birthday is in May so he will be 24 by the start of his 3rd year. We have an option for a 5th year (which we will most certainly take if we don't reach an extension) on his rookie deal. That would put him at age 25 in year 4 and 26 in year 5.
There is no "max" on the number of times a certain player can be franchised. The amount of the tag increases with each consecutive year that the player has been tagged but you can continue to tag them as long as you want.
Year 1 of the franchise tag - Cam will be 27
Year 2 of the franchise tag (at a price of 120% of the previous year) - Cam will be 28
Year 3 of the franchise tag (at a price of 140% of the previous year) - Cam will be 29
Year 4 on the tag would be something like 160% of the previous year value, which would almost certainly be too high of a price to pay for any player that will be 30 years old when the season starts.