First of all, you are super ambitious to to have never designed a transformer before and now you are designing a phase modulated full bridge converter at 2.1kW!
1. In a FB phase shifted topology you don't want the resonant inductor in the transformer itself or the secondary ringing voltage will kill your output diodes. You want the resonant inductor to be external and be clamped to the rails via a pair of fast recovery diodes. This is commonly done with this topology and for good reason. This is a quasi resonant topology, not fully resonant.
2. I doubt you will find the required inductor off the shelf (and why anyway?). If you wind it yourself you have much more freedom with its value.
An ETD49 will probably be a little small at 2.1kW and 100kHz, but it's not impossible.
Try to reduce your leakage inductance as much as possible by interleaving the windings. Even then I would expect you to have serious ringing on the output diodes, so cater for some snubbers now.
Also, opt for current mode control as it gives you much more control, particularly under fault conditions.
Dick